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844 lines
18 KiB
844 lines
18 KiB
;-----------------------------------------------------------------------------
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;
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; Overlay for ZMP (Z-Modem Program)
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;
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; Name ZMO-WBW.Z80
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;
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; Dated April 14, 2025
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;
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; Written by -
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; Phil Summers, Wayne Warthen
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;
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; ROMWBW version using HBIOS and https://github.com/mecparts/zmp
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; version of zmodem
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;
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; - All modem/serial i/o is through RomWBW HBIOS.
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;
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; - Data bits, stop bits, and parity are determined by HBIOS.
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; The ZMP settings will have no effect. Use RomWBW MODE
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; command to set serial port config before starting ZMP.
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;
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; - Timing delay calculations based on HBIOS reported CPU speed.
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;
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; - The pcfg equate determines whether the overlay will
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; implement port initialization. Normally, pcfg will be
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; set to false because ZMP does not allow configuring
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; many HBIOS speeds (notably the 115200 baud hardwired
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; into many RCBus systems). In this case, you must
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; configure the modem port using the RomWBW
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; MODE command as desired before starting ZMP.
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;
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; - The modem port is assigned to an HBIOS character unit. By
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; default, the modem is assigned to HBIOS character unit 1.
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; An alternate HBIOS character unit may be specified as a
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; parameter on the command line as a single number. For
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; example, the following will assign HBIOS port 3 as the
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; ZMP modem port:
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;
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; ZMP 3
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;
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; - The original version of ZMP from Ron Murray allows you to
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; select from 2 logical modem ports. This overlay ignores
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; any attempt to select ports from within ZMP. The desired
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; modem port should be assigned using the command line
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; parameter as described above.
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;
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; - Teraterm users may need to change the ZmodemWinSize value
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; to 1024 in the teraterm.ini configuration file.
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;
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;-----------------------------------------------------------------------------
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;
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;
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; System-dependent code overlay for ZMODEM
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;
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;
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;
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; Insert your own code as necessary in this file. Code contained herein
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; has been written in Z80 code for use with M80 or SLR. Assemble as follows:
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;
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; SLR ZMO-xx01/h
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; MLOAD ZMP.COM=ZMODEM.COM,ZMO-xx01.HEX
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; or
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; M80 =ZMO-xx01.Z80
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; RELHEX ZMO-xx01
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; MLOAD ZMP.COM=ZMODEM.COM,ZMO-xx01.HEX
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;
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;
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; (Don't use L80 without changing the source for assembly as a
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; cseg file.)
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;
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;-----------------------------------------------------------------------------
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;
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;
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; Notes on modifying this file:
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;
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; C requires that functions do not change either index register (IX or IY).
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; If your overlay requires either of these to be changed, ensure they are
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; restored to the original values on return.
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; Since collecting parameters from C functions can be tricky, only change
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; the parts marked 'Insert your own code here'. Do NOT modify the jump
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; table at the start. Do NOT modify the entry/exit sections of each
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; function. Do NOT pass 'GO'. Do NOT collect $200.
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; Apart from defining modem functions, this file also defines terminal
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; characteristics. Examples provided are for ADM-3A (with a few of my own
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; additions). Modify to suit your own terminal. An inline print routine
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; is provided for printing strings in the usual way: usage is
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;
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; call print
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; db 'required string',0
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;
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;-----------------------------------------------------------------------------
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;
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;
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; Don't forget to set your clock speed at the clkspd variable.
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;
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;
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; If you find your overlay exceeds the maximum size (currently 0400h),
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; you will have to contact me for another version. If too many people need
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; to do it, we haven't allowed enough room.
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;
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; Ron Murray 15/8/88
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;
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;
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;
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;---------------------------------------------------------------------------
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false equ 0
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true equ not false
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;------------------------------------------------------------------------------
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; User-set variables:
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debug equ false ; to allow debugging of overlay with Z8E etc.
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clkspd equ 8 ; Processor clock speed in MHz
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pcfg equ false ; Allow ZMP to configure port
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;
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;Set the following two equates to the drive and user area which will contain
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; ZMP's .OVR files, .CFG file, .FON file and .HLP file. Set both to zero
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; (null) to locate them on the drive from which ZMP was invoked.
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overdrive equ 0 ; Drive to find overlay files on ('A'-'P')
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overuser equ 0 ; User area to find files
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;------------------------------------------------------------------------------
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; NOT user-set variables
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userdef equ 0145h ; origin of this overlay
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; This address should not change with
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; subsequent revisions.
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mspeed equ 03ch ; location of current baud rate.
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ovsize equ 0400h ; max size of this overlay
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fcb equ 05ch ; primary command line CP/M fcb
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.z80 ; use z80 code
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aseg ; absolute
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if debug
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org 100h ; so you can debug it with cebug, zsid, etc
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else
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org userdef
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endif
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esc equ 1bh
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ctrlq equ 11h
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cr equ 0dh
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lf equ 0ah
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bdos equ 5
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codebgn equ $
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;Jump table for the overlay: do NOT change this
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jump_tab:
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jp scrnpr ; screen print
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jp mrd ; modem read with timeout
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jp mchin ; get a character from modem
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jp mchout ; send a character to the modem
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jp mordy ; test for tx buffer empty
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jp mirdy ; test for character received
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jp sndbrk ; send break
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jp cursadd ; cursor addressing
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jp cls ; clear screen
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jp invon ; inverse video on
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jp invoff ; inverse video off
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jp hide ; hide cursor
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jp show ; show cursor
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jp savecu ; save cursor position
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jp rescu ; restore cursor position
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jp mint ; service modem interrupt
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jp invec ; initialise interrupt vectors
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jp dinvec ; de-initialise interrupt vectors
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jp mdmerr ; test uart flags for error
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jp dtron ; turn DTR on
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jp dtroff ; turn DTR OFF
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jp init ; initialise uart
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jp wait ; wait seconds
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jp mswait ; wait milliseconds
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jp userin ; user-defined entry routine
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jp userout ; user-defined exit routine
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jp getvars ; get system variables
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jp setport ; set port (0 or 1)
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; Spare jumps for compatibility with future versions
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jp spare ; spare for later use
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jp spare ; spare for later use
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jp spare ; spare for later use
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jp spare ; spare for later use
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jp spare ; spare for later use
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jp spare ; spare for later use
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; Local storage
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hbunit db 1 ; Active HBIOS unit for modem I/O
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cpumhz db clkspd ; CPU clock speed in MHz
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;
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; Main code starts here
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;
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;Screen print function
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scrnpr:
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; <== Insert your own code here
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call print
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db 'Screen print not supported.',cr,lf,0
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; <== End of your own code
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spare:
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ret
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; User-defined entry routine: leave empty if not needed
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userin:
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push bc
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push de
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push hl
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call print
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db cr,lf,'ZMP Overlay for RomWBW HBIOS v1.0',cr,lf,0
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; Scan and parse default FCB to initialize HBIOS unit if
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; specified.
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ld a,(fcb + 1) ; get parm from fcb
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cp ' ' ; anything there?
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jr z,userin1 ; if empty, done
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sub '0' ; ASCII to binary
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jr c,parmerr ; less than 0, parm error
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cp 10 ; >= 10?
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jr nc,parmerr ; greater than 9, parm error
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ld (hbunit),a ; save it
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userin1:
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call showcom ; show com port info
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; check that unit is actually available in HBIOS
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ld bc,0f800h ; get HBIOS char unit count
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rst 8 ; do it
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ld a,(hbunit) ; get active modem unit
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cp e ; compare to units available
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jr nc,porterr ; unit too high, port error
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if pcfg
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; Force port initialization by setting an invalid
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; baud rate (mspeed).
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; speed to an arbitrary value of 8 (9600 baud).
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ld a,-1
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ld (mspeed),a
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else
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; We don't support port configuration. Here we set the modem
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; speed to an arbitrary value of 8 (9600 baud).
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ld a,8
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ld (mspeed),a
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endif
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ld bc,0f8f0h ; HBIOS func get CPU info
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rst 08 ; do it, l = CPU speed in MHz
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ld a,l ; to accum
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ld (cpumhz),a ; and save it for wait loop
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ld hl,2
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call waithls
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pop hl
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pop de
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pop bc
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ret
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parmerr:
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; Handle a bad parameter
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call print ; print error message
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db cr,lf,'ZMP parameter error!',cr,lf,0
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rst 0 ; bail out to OS
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porterr:
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; Handle a bad port
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call print ; print error message
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db cr,lf,'Invalid HBIOS unit for ZMP Modem port!',cr,lf,0
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rst 0 ; bail out to OS
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showcom:
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; Display the HBIOS unit to be used for the ZMP Modem
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call print
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db cr,lf,'ZMP Modem on HBIOS Unit #',0
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ld a,(hbunit)
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add a,'0'
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call cout
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call print
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db cr,lf,0
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; User-defined exit routine: leave empty if not needed
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userout:
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ret
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;Get a character from the modem: return in HL
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mchin:
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push bc
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; <== Insert your own code here
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ld a,(hbunit)
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ld c,a
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ld b,00h
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rst 08
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ld a,e
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; <== End of your own code
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ld l,a ; put in HL
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ld h,0
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or a ; set/clear Z
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pop bc
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ret
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;Send a character to the modem
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mchout:
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ld hl,2 ; get the character
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add hl,sp
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ld a,(hl)
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; <== Insert your own code here
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push bc
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ld e,a
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ld a,(hbunit)
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ld c,a
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ld b,01h
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rst 08
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pop bc
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; <== End of your own code
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ret ; done
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;Test for output ready: return TRUE (1) in HL if ok
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mordy:
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; <== Insert your own code here
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push bc
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ld a,(hbunit)
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ld c,a
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ld b,03h
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rst 08
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ld h,0
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ld l,a
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pop bc
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; <== End of your own code
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ld a,l ; set/clear Z
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or a
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ret
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;Test for character at modem: return TRUE (1) in HL if so
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mirdy:
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; <== Insert your own code here
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push bc
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ld a,(hbunit)
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ld c,a
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ld b,02h
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rst 08
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ld h,0
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ld l,a
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pop bc
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; <== End of your own code
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ld a,l ; set/clear Z
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or a
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ret
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;Send a break to the modem: leave empty if your system can't do it
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sndbrk:
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; <== Insert your own code here
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ld hl,300 ; wait 300 mS
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call waithlms
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; <== End of your own code
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ret
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;
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;Test UART flags for error: return TRUE (1) in HL if error.
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mdmerr:
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; <== Insert your own code here
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xor a ; not implemented
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; <== End of your own code
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ld a,l ; set/clear Z
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or a
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ret
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|
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;Turn DTR ON
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dtron:
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; <== Insert your own code here
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; <== End of your own code
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ret
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;Turn DTR OFF
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dtroff:
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; <== Insert your own code here
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; <== End of your own code
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ret
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;Initialise the uart
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init:
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ld hl,2 ; get parameters
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add hl,sp
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ex de,hl
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call getparm ; in HL
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ld (brate),hl ; baud rate
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call getparm
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ld (parity),hl ; parity
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call getparm
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ld (data),hl ; data bits (BINARY 7 or 8)
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call getparm
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ld (stop),hl ; stop bits (BINARY 1 or 2)
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; <== Insert your own code here
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; using values below
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; don't forget to load mspeed with the
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; current brate value if the new rate is
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; valid. See table of values below.
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push bc
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; If pcfg is true, attempt to initialize the active
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; HBIOS unit. If false, initialization if bypassed with
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; the assumption that the RomWBW MODE command was used
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; to initialize the port priot to running ZMP.
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if pcfg
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call print
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db 'Initializing device: ',0
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call diport
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ld a,(hbunit) ; get device type
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ld c,a
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ld b,06h
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rst 08
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or a ; check if valid
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jr nz,initerr
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ld a,(brate) ; get baud rate to set
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ld c,a
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ld b,0
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ld hl,baudtbl
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add hl,bc
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ld a,(hl) ; convert to encoded hbios
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cp a,-1
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jr z,initerr
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push af
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ld a,(hbunit) ; get line characteristics
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ld c,a
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ld b,05h
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rst 08
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ld a,d ; mask out exisitng
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and 11100000b ; replace with rate
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ld d,a
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pop af
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or d
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ld d,a
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ld b,04h ; set new
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ld a,(hbunit) ; speed
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ld c,a
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rst 08
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or a
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jr nz,initerr
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ld a,(brate) ; load mspeed with the current brate value if
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ld (mspeed),a ; the new rate is valid. See table of values below.
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call print
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db lf,lf,'Initization completed, device: ',0
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call diport
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jr init_z
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initerr:call print
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db lf,lf,'Initization failed, device: ',0
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call diport
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|
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jr init_z
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|
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diport: ld a,(hbunit) ; Display port
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diport1:add a,'0'
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call cout
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call print
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|
db cr,lf,0
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ld hl,2
|
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call waithls
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ret
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|
else
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|
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;call print
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;db cr,lf,'Modem port initialization...',0
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;ld hl,2
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;call waithls
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|
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ld b,05h ; HBIOS port reset function
|
|
ld a,(hbunit) ; get active modem port
|
|
ld c,a ; and put in accum
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rst 8 ; reset port
|
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or a ; check result
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jr nz,init1 ; if error, handle it
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|
ld a,8 ; dummy value for speed
|
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ld (mspeed),a ; save it
|
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jr init_z ; done
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|
|
init1:
|
|
; Handle error return from initialization
|
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call print
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db cr,lf,'Modem port initialization failed!',cr,lf,0
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ld hl,2
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call waithls
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|
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jr init_z
|
|
|
|
endif
|
|
|
|
init_z:
|
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pop bc
|
|
|
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; <== End of your own code
|
|
|
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ret
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;--------------------------------------------------------------------------
|
|
|
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stop: dw 1 ; stop bits
|
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parity: dw 'N' ; parity
|
|
data: dw 8 ; data bits
|
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brate: dw 7 ; baud rate:
|
|
|
|
;--------------------------------------------------------------------------
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;
|
|
;Values of brate for each baud rate
|
|
;
|
|
; hb encode baud rate brate
|
|
;
|
|
baudtbl:
|
|
db -1 ; 110 0 not supported
|
|
db 2 ; 300 1
|
|
db 17 ; 450 2
|
|
db 3 ; 600 3
|
|
db -1 ; 710 4 not supported
|
|
db 4 ; 1200 5
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|
db 5 ; 2400 6
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db 6 ; 4800 7
|
|
db 7 ; 9600 8
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db 8 ; 19200 9
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db 9 ; 38400 10
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|
db 24 ; 57600 11
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|
db 10 ; 76800 12
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;
|
|
; Set the port. ZMP supplies either 0 or 1 as a parameter. You're on your
|
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; own here -- your system is bound to be different from any other! You may
|
|
; implement a software switch on all the modem-dependent routines, or perhaps
|
|
; you can have one or two centralised routines for accessing the UARTs and
|
|
; modify the code from this routine to select one or the other. (Who said
|
|
; there was anything wrong with self-modifying code?). If you have only one
|
|
; UART port, or if you don't want to go through all the hassles, just have
|
|
; this routine returning with no changes made. Note that ZMP calls this
|
|
; routine with both values for the port on initialisation.
|
|
;
|
|
; Only originl ZMP calls setport. MECPARTS variant does not.
|
|
;
|
|
; We ignore this call. Since we are using a command line parameter
|
|
; to specify the desired modem port, it makes no sense.
|
|
;
|
|
setport:
|
|
ld hl,2 ; get port number
|
|
add hl,sp
|
|
ex de,hl
|
|
call getparm ; in HL (values are 0 and 1)
|
|
|
|
; <== Insert your own code here
|
|
|
|
; <== End of your own code
|
|
|
|
ret
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|
|
|
|
;
|
|
;****************************************************************************
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;Video terminal sequences: these are for VT-100: Modify as you wish
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;Cursor addressing:
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cursadd:
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ld hl,2 ; get parameters
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add hl,sp
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ex de,hl
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call getparm ; in HL
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inc hl
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ld (row),hl ; row
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call getparm
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inc hl
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ld (col),hl ; column
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;
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push bc
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call print
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db esc,'[',0
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ld a,(row) ; row first
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call cursconv
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ld a,';'
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call cout
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ld a,(col) ; same for column
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call cursconv
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ld a,'H'
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call cout
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pop bc
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ret
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;
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cursconv:
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ld b,a
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xor a
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ca1: add a,1
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daa
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djnz ca1
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ld (num),a
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and 0f0h
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jr z,ca2
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srl a
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srl a
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srl a
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srl a
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or '0'
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call cout
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ca2: ld a,(num)
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and 0fh
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or '0'
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call cout
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ret
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;
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row: ds 2 ; row
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col: ds 2 ; column
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num: ds 1
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;
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;Clear screen:
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cls:
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call print
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db esc,"[H",esc,"[2J",0
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ret
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;
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;Inverse video on:
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invon:
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call print
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|
db esc,"[7m",0
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|
ret
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|
;
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|
;Inverse video off:
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|
invoff:
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|
call print
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|
db esc,"[m",0
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|
ret
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|
;
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|
;Turn off cursor:
|
|
hide:
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|
call print
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|
db esc,'[?25l',0
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|
ret
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|
;
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|
;Turn on cursor:
|
|
show:
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|
call print
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|
db esc,'[?25h',0
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|
ret
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|
;
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|
;Save cursor position:
|
|
savecu:
|
|
call print
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|
db esc,'[7',0
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|
ret
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|
;
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|
;Restore cursor position:
|
|
rescu:
|
|
call print
|
|
db esc,'[8',0
|
|
ret
|
|
|
|
;****************************************************************************
|
|
|
|
;Service modem interrupt:
|
|
mint:
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|
ret ; handled in HBIOS
|
|
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|
;Initialise interrupt vectors:
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|
invec:
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|
ret ; ditto
|
|
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|
;De-initialise interrupt vectors:
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|
dinvec:
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|
ret ; ditto
|
|
|
|
;****************** End of user-defined code ********************************
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|
; Do not change anything below here.
|
|
|
|
;Modem character test for 100 ms
|
|
mrd:
|
|
push bc ; save bc
|
|
ld bc,100 ; set limit
|
|
mrd1:
|
|
call mirdy ; char at modem?
|
|
jr nz,mrd2 ; yes, exit
|
|
ld hl,1 ; else wait 1ms
|
|
call waithlms
|
|
dec bc ; loop till done
|
|
ld a,b
|
|
or c
|
|
jr nz,mrd1
|
|
ld hl,0 ; none there, result=0
|
|
xor a
|
|
mrd2:
|
|
pop bc
|
|
ret
|
|
|
|
; Inline print routine: destroys A and HL
|
|
|
|
print:
|
|
ex (sp),hl ; get address of string
|
|
ploop:
|
|
ld a,(hl) ; get next
|
|
inc hl ; bump pointer
|
|
or a ; done if zero
|
|
jr z,pdone
|
|
call cout ; else print
|
|
jr ploop ; and loop
|
|
pdone:
|
|
ex (sp),hl ; restore return address
|
|
ret ; and quit
|
|
|
|
;
|
|
;Output a character in A to the console
|
|
;
|
|
cout:
|
|
push bc ; save regs
|
|
push de
|
|
push hl
|
|
ld e,a ; character to E
|
|
ld c,2
|
|
call bdos ; print it
|
|
pop hl
|
|
pop de
|
|
pop bc
|
|
ret
|
|
|
|
|
|
;Wait seconds
|
|
wait:
|
|
ld hl,2
|
|
add hl,sp
|
|
ex de,hl ; get delay size
|
|
call getparm
|
|
; fall thru to..
|
|
;Wait seconds in HL
|
|
waithls:
|
|
push hl ; save loop control
|
|
ld hl,1000 ; 1000ms = 1 second
|
|
call waithlms
|
|
pop hl ; restore loop control
|
|
dec hl
|
|
ld a,h
|
|
or l
|
|
jr nz,waithls
|
|
ret
|
|
|
|
|
|
|
|
;Wait milliseconds
|
|
mswait:
|
|
ld hl,2
|
|
add hl,sp
|
|
ex de,hl ; get delay size
|
|
call getparm
|
|
; fall thru to..
|
|
;Wait milliseconds in HL
|
|
waithlms:
|
|
; burn 1000us (1ms)
|
|
ld a,(cpumhz)
|
|
ld e,a
|
|
hlms1:
|
|
; burn 1000 t-states
|
|
; 50 * 20 = 1000 t-states
|
|
ld d,50
|
|
hlms2:
|
|
nop ; 4
|
|
dec d ; 4
|
|
jr nz,hlms2 ; 12 20
|
|
|
|
dec e
|
|
jr nz,hlms1
|
|
|
|
dec hl
|
|
ld a,h
|
|
or l
|
|
jr nz,waithlms
|
|
|
|
ret
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
;Get next parameter from (de) into hl
|
|
getparm:
|
|
ex de,hl ; get address into hl
|
|
ld e,(hl) ; get lo
|
|
inc hl
|
|
ld d,(hl) ; then hi
|
|
inc hl ; bump for next
|
|
ex de,hl ; result in hl, address still in de
|
|
ret
|
|
|
|
;Get address of user-defined variables
|
|
|
|
getvars:
|
|
ld hl,uservars
|
|
ret
|
|
|
|
uservars:
|
|
dw overdrive ; .OVR etc. drive/user
|
|
dw overuser
|
|
|
|
|
|
if ($ - codebgn) gt ovsize
|
|
toobig: jp errval ; Overlay too large!
|
|
endif
|
|
|
|
end
|
|
|