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160 lines
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;
;==================================================================================================
; CH376 NATIVE USB KEYBOARD DRIVER
;==================================================================================================
;
#DEFINE DEFM .DB
#DEFINE DEFB .DB
#DEFINE DEFW .DW
#IF (SYSTIM == TM_NONE)
.ECHO "*** ERROR: MKY REQUIRES SYSTEM TIMER -- NONE CONFIGURED!!!\n"
!!! ; FORCE AN ASSEMBLY ERROR
#ENDIF
#include "./ch376-native/keyboard.s"
; COUNT FOR INTERRUPT HANDLER TO TRIGGER KEYBOARD SCANNER (EG: SCAN KEYBOARD ONLY EVERY 3RD INTERRUPT (3/60))
SCAN_INT_PERIOD: .EQU 3
; VDP-INTERUPT COUNTER THAT COUNTS FROM SCAN_INT_PERIOD TO 0, WHEN IT REACHES ZERO, THE
; KEYBOARD MATRIX IS SCANNED, AND THE COUNTERS IS RESET AT SCAN_INT_PERIOD
UKY_SCNCNT: .DB SCAN_INT_PERIOD
.DB 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
.DB 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
.DB 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
.DB 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
.DB 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
.DB 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
.DB 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
.DB 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
.DB 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
.DB 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
.DB 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
.DB 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
.DB 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
.DB 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
.DB 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
.DB 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
UKY_INTSTK: ; 128 bytes for keyboard interrupt stack - need ~52 bytes???
CHUKB_INIT:
; INSTALL INTERRUPT HANDLER
LD HL, (VEC_TICK+1)
LD (VEC_CHUKB_TICK+1), HL
LD HL, CHUKB_TICK
LD (VEC_TICK+1), HL
JP _keyboard_init
CHUKB_TICK:
LD A, (UKY_SCNCNT) ; SCAN THE KEYBOARD EVERY 'SCAN_INT_PERIOD' INTERRUPTS.
DEC A
LD (UKY_SCNCNT), A
JR NZ, VEC_CHUKB_TICK
LD A, SCAN_INT_PERIOD
LD (UKY_SCNCNT), A
; we gonna need a bigger stack
EZ80_UTIL_DEBUG
LD (UKY_INT_SP),SP ; SAVE ORIGINAL STACK FRAME
LD SP,UKY_INTSTK ; USE DEDICATED INT STACK FRAME IN HI MEM
CALL _keyboard_tick
LD SP, $FFFF ; RESTORE ORIGINAL STACK FRAME
UKY_INT_SP .EQU $ - 2
;
VEC_CHUKB_TICK:
JP HB_TICK
; ### Function 0x4C -- Keyboard Status (VDAKST)
;
; Inputs:
; None
;
; Outputs:
; A: Status / Codes Pending
;
; Return a count of the number of key Codes Pending (A) in the keyboard buffer.
; If it is not possible to determine the actual number in the buffer, it is
; acceptable to return 1 to indicate there are key codes available to read and
; 0 if there are none available.
; The value returned in register A is used as both a Status (A) code and the
; return value. Negative values (bit 7 set) indicate a standard HBIOS result
; (error) code. Otherwise, the return value represents the number of key codes
; pending.
;
UKY_STAT:
JP _keyboard_buf_size
; ### Function 0x4D -- Video Keyboard Flush (VDAKFL)
;
; Inputs:
; C: Video Unit
;
; Outputs:
; A: standard HBIOS result code
;
; Purged and all contents discarded. The Status (A) is a standard HBIOS result code.
;
UKY_FLUSH:
CALL _keyboard_buf_flush
XOR A
RET
;
; ### Function 0x4E -- Video Keyboard Read (VDAKRD)
;
; Inputs:
; None
;
; Outputs:
; A: Status
; C: Scancode
; D: Keystate
; E: Keycode
;
; Read the next key data from the keyboard. If a buffer is used, return the next key code in the buffer.
; If no key data is available, this function will wait indefinitely for a keypress. The Status (A) is a
; standard HBIOS result code.
;
; The Scancode (C) value is the raw scancode from the keyboard for the keypress. Scancodes are from
; the PS/2 scancode set 2 standard.
;
; The Keystate (D) is a bitmap representing the value of all modifier keys and shift states as they
; existed at the time of the keystroke. The bitmap is defined as:
;
; Bit Keystate Indication
; 7 Key pressed was from the num pad
; 6 Caps Lock was active
; 5 Num Lock was active
; 4 Scroll Lock was active
; 3 Windows key was held down
; 2 Alt key was held down
; 1 Control key was held down
; 0 Shift key was held down
;
; The Keycode (E) is generally returned as appropriate ASCII values, if possible. Special keys, like
; function keys and arrows, are returned as reserved codes as described at the start of this section.
;
UKY_READ:
HB_DI
CALL _keyboard_buf_get_next
HB_EI
LD A, H
OR A
JR NZ, UKY_READ
LD C, 0
LD D, 0
; LD E, 'A'
XOR A
RET