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662 lines
18 KiB
662 lines
18 KiB
;
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;==================================================================================================
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; UART DRIVER (SERIAL PORT)
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;==================================================================================================
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;
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; SETUP PARAMETER WORD:
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; +-------+---+-------------------+ +---+---+-----------+---+-------+
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; | |RTS| ENCODED BAUD RATE | |DTR|XON| PARITY |STP| 8/7/6 |
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; +-------+---+---+---------------+ ----+---+-----------+---+-------+
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; F E D C B A 9 8 7 6 5 4 3 2 1 0
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; -- MSB (D REGISTER) -- -- LSB (E REGISTER) --
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;
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; UART CONFIGURATION REGISTERS:
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; +-------+---+-------------------+ +---+---+-----------+---+-------+
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; | 0 0 |AFE|LP OT2 OT1 RTS DTR| |DLB|BRK|STK EPS PEN|STB| WLS |
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; +-------+---+-------------------+ +---+---+-----------+---+-------+
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; F E D C B A 9 8 7 6 5 4 3 2 1 0
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; -- MCR -- -- LCR --
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;
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;
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UART_DEBUG .EQU FALSE
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;
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UART_NONE .EQU 0 ; UNKNOWN OR NOT PRESENT
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UART_8250 .EQU 1
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UART_16450 .EQU 2
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UART_16550 .EQU 3
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UART_16550A .EQU 4
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UART_16550C .EQU 5
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UART_16650 .EQU 6
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UART_16750 .EQU 7
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UART_16850 .EQU 8
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;
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UART_RBR .EQU 0 ; DLAB=0: RCVR BUFFER REG (READ)
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UART_THR .EQU 0 ; DLAB=0: XMIT HOLDING REG (WRITE)
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UART_IER .EQU 1 ; DLAB=0: INT ENABLE REG (READ)
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UART_IIR .EQU 2 ; INT IDENT REGISTER (READ)
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UART_FCR .EQU 2 ; FIFO CONTROL REG (WRITE)
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UART_LCR .EQU 3 ; LINE CONTROL REG (READ/WRITE)
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UART_MCR .EQU 4 ; MODEM CONTROL REG (READ/WRITE)
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UART_LSR .EQU 5 ; LINE STATUS REG (READ)
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UART_MSR .EQU 6 ; MODEM STATUS REG (READ)
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UART_SCR .EQU 7 ; SCRATCH REGISTER (READ/WRITE)
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UART_DLL .EQU 0 ; DLAB=1: DIVISOR LATCH (LS) (READ/WRITE)
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UART_DLM .EQU 1 ; DLAB=1: DIVISOR LATCH (MS) (READ/WRITE)
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UART_EFR .EQU 2 ; LCR=$BF: ENHANCED FEATURE REG (READ/WRITE)
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;;
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;UART_FIFO .EQU 0 ; FIFO ENABLE BIT
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;UART_AFC .EQU 1 ; AUTO FLOW CONTROL ENABLE BIT
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;
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#DEFINE UART_INP(RID) CALL UART_INP_IMP \ .DB RID
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#DEFINE UART_OUTP(RID) CALL UART_OUTP_IMP \ .DB RID
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;
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;
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;
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UART_PREINIT:
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;
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; INIT UART4 BOARD CONFIG REGISTER (NO HARM IF IT IS NOT THERE)
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;
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LD A,$80 ; SELECT 7.3728MHZ OSC & LOCK CONFIG REGISTER
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OUT ($CF),A ; DO IT
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;
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; SETUP THE DISPATCH TABLE ENTRIES
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;
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LD B,UART_CNT ; LOOP CONTROL
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LD C,0 ; PHYSICAL UNIT INDEX
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XOR A ; ZERO TO ACCUM
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LD (UART_DEV),A ; CURRENT DEVICE NUMBER
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UART_PREINIT0:
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PUSH BC ; SAVE LOOP CONTROL
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LD A,C ; PHYSICAL UNIT TO A
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RLCA ; MULTIPLY BY CFG TABLE ENTRY SIZE (8 BYTES)
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RLCA ; ...
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RLCA ; ... TO GET OFFSET INTO CFG TABLE
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LD HL,UART_CFG ; POINT TO START OF CFG TABLE
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CALL ADDHLA ; HL := ENTRY ADDRESS
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PUSH HL ; SAVE IT
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PUSH HL ; COPY CFG DATA PTR
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POP IY ; ... TO IY
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CALL UART_INITUNIT ; HAND OFF TO GENERIC INIT CODE
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POP DE ; GET ENTRY ADDRESS BACK, BUT PUT IN DE
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POP BC ; RESTORE LOOP CONTROL
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;
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LD A,(IY + 1) ; GET THE UART TYPE DETECTED
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OR A ; SET FLAGS
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JR Z,UART_PREINIT2 ; SKIP IT IF NOTHING FOUND
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;
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PUSH BC ; SAVE LOOP CONTROL
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LD BC,UART_FNTBL ; BC := FUNCTION TABLE ADDRESS
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CALL NZ,CIO_ADDENT ; ADD ENTRY IF UART FOUND, BC:DE
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POP BC ; RESTORE LOOP CONTROL
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;
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UART_PREINIT2:
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INC C ; NEXT PHYSICAL UNIT
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DJNZ UART_PREINIT0 ; LOOP UNTIL DONE
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XOR A ; SIGNAL SUCCESS
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RET ; AND RETURN
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;
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; UART INITIALIZATION ROUTINE
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;
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UART_INITUNIT:
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; DETECT THE UART TYPE
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CALL UART_DETECT ; DETERMINE UART TYPE
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LD (IY + 1),A ; ALSO SAVE IN CONFIG TABLE
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OR A ; SET FLAGS
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RET Z ; ABORT IF NOTHING THERE
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; UPDATE WORKING UART DEVICE NUM
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LD HL,UART_DEV ; POINT TO CURRENT UART DEVICE NUM
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LD A,(HL) ; PUT IN ACCUM
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INC (HL) ; INCREMENT IT (FOR NEXT LOOP)
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LD (IY),A ; UDPATE UNIT NUM
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; SET DEFAULT CONFIG
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LD DE,-1 ; LEAVE CONFIG ALONE
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JP UART_INITDEV ; IMPLEMENT IT AND RETURN
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;
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;
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;
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UART_INIT:
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LD B,UART_CNT ; COUNT OF POSSIBLE UART UNITS
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LD C,0 ; INDEX INTO UART CONFIG TABLE
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UART_INIT1:
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PUSH BC ; SAVE LOOP CONTROL
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LD A,C ; PHYSICAL UNIT TO A
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RLCA ; MULTIPLY BY CFG TABLE ENTRY SIZE (8 BYTES)
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RLCA ; ...
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RLCA ; ... TO GET OFFSET INTO CFG TABLE
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LD HL,UART_CFG ; POINT TO START OF CFG TABLE
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CALL ADDHLA ; HL := ENTRY ADDRESS
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PUSH HL ; COPY CFG DATA PTR
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POP IY ; ... TO IY
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LD A,(IY + 1) ; GET UART TYPE
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OR A ; SET FLAGS
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CALL NZ,UART_PRTCFG ; PRINT IF NOT ZERO
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POP BC ; RESTORE LOOP CONTROL
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INC C ; NEXT UNIT
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DJNZ UART_INIT1 ; LOOP TILL DONE
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;
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XOR A ; SIGNAL SUCCESS
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RET ; DONE
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;
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; DRIVER FUNCTION TABLE
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;
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UART_FNTBL:
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.DW UART_IN
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.DW UART_OUT
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.DW UART_IST
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.DW UART_OST
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.DW UART_INITDEV
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.DW UART_QUERY
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.DW UART_DEVICE
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#IF (($ - UART_FNTBL) != (CIO_FNCNT * 2))
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.ECHO "*** INVALID UART FUNCTION TABLE ***\n"
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#ENDIF
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;
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;
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;
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UART_IN:
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CALL UART_IST ; RECEIVED CHAR READY?
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JR Z,UART_IN ; LOOP IF NOT
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LD C,(IY + 2) ; C := BASE UART PORT (WHICH IS ALSO RBR REG)
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IN E,(C) ; CHAR READ TO E
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XOR A ; SIGNAL SUCCESS
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RET ; AND DONE
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;
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;
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;
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UART_OUT:
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CALL UART_OST ; READY FOR CHAR?
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JR Z,UART_OUT ; LOOP IF NOT
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LD C,(IY + 2) ; C := BASE UART PORT (WHICH IS ALSO THR REG)
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OUT (C),E ; SEND CHAR FROM E
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XOR A ; SIGNAL SUCCESS
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RET
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;
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;
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;
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UART_IST:
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LD C,(IY + 3) ; C := LINE STATUS REG (LSR)
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IN A,(C) ; GET STATUS
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AND $01 ; ISOLATE BIT 0 (RECEIVE DATA READY)
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JP Z,CIO_IDLE ; NOT READY, RETURN VIA IDLE PROCESSING
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XOR A ; ZERO ACCUM
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INC A ; ACCUM := 1 TO SIGNAL 1 CHAR WAITING
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RET ; DONE
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;
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;
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;
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UART_OST:
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LD C,(IY + 3) ; C := LINE STATUS REG (LSR)
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IN A,(C) ; GET STATUS
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AND $20 ; ISOLATE BIT 5 ()
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JP Z,CIO_IDLE ; NOT READY, RETURN VIA IDLE PROCESSING
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XOR A ; ZERO ACCUM
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INC A ; ACCUM := 1 TO SIGNAL 1 BUFFER POSITION
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RET ; DONE
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;
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;
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;
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UART_INITDEV:
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; TEST FOR -1 WHICH MEANS USE CURRENT CONFIG (JUST REINIT)
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LD A,D ; TEST DE FOR
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AND E ; ... VALUE OF -1
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INC A ; ... SO Z SET IF -1
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JR NZ,UART_INITDEV1 ; IF DE == -1, REINIT CURRENT CONFIG
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;
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; LOAD EXISTING CONFIG TO REINIT
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LD E,(IY + 4) ; LOW BYTE
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LD D,(IY + 5) ; HIGH BYTE
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;
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UART_INITDEV1:
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; DETERMINE DIVISOR
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PUSH DE ; SAVE CONFIG
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CALL UART_COMPDIV ; COMPUTE DIVISOR TO BC
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POP DE ; RESTORE CONFIG
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RET NZ ; ABORT IF COMPDIV FAILS!
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;
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; GOT A DIVISOR, COMMIT NEW CONFIG
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LD (IY + 4),E ; SAVE LOW WORD
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LD (IY + 5),D ; SAVE HI WORD
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;
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; START OF ACTUAL UART CONFIGURATION
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LD A,80H ; DLAB IS BIT 7 OF LCR
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UART_OUTP(UART_LCR) ; DLAB ON
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LD A,B
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UART_OUTP(UART_DLM) ; SET DIVISOR (MS)
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LD A,C
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UART_OUTP(UART_DLL) ; SET DIVISOR (LS)
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;
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; FOR 750+, WE ENABLE THE 64-BYTE FIFO
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; DLAB MUST STILL BE ON FOR ACCESS TO BIT 5
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; WE DO *NOT* ENABLE ANY OTHER FCR BITS HERE
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; BEACAUSE IT WILL SCREW UP THE 2552!!!
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LD A,%00100000
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UART_OUTP(UART_FCR) ; DO IT
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;
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XOR A ; DLAB OFF NOW
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UART_OUTP(UART_LCR) ; DO IT
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;
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; SETUP FCR, BIT 5 IS KEPT ON EVEN THOUGH IT IS PROBABLY
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; IRRELEVANT BECAUSE IT ONLY APPLIES TO 750 AND DLAB IS
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; NOW OFF, BUT DOESN'T HURT.
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LD A,%00100111 ; FIFO ENABLE & RESET
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UART_OUTP(UART_FCR) ; DO IT
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;
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; SETUP LCR FROM SECOND CONFIG BYTE
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LD A,(IY + 4) ; GET CONFIG BYTE
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AND ~$C0 ; ISOLATE PARITY, STOP/DATA BITS
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UART_OUTP(UART_LCR) ; SAVE IT
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;
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; SETUP MCR FROM FIRST CONFIG BYTE
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LD A,(IY + 5) ; GET CONFIG BYTE
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AND ~$1F ; REMOVE ENCODED BAUD RATE BITS
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OR $03 ; FORCE RTS & DTR
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UART_OUTP(UART_MCR) ; SAVE IT
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;
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; TEST FOR EFR CAPABLE CHIPS
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LD A,(IY + 1) ; GET UART TYPE
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CP UART_16650 ; 16650?
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JR Z,UART_INITDEV2 ; USE EFR REGISTER
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CP UART_16850 ; 16850?
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JR Z,UART_INITDEV2 ; USE EFR REGISTER
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JR UART_INITDEV4 ; NO EFR, SKIP AHEAD
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;
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UART_INITDEV2:
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; WE HAVE AN EFR CAPABLE CHIP, SET EFR REGISTER
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UART_INP(UART_LCR) ; GET CURRENT LCR VALUE
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PUSH AF ; SAVE IT
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LD A,$BF ; VALUE TO ACCESS EFR
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UART_OUTP(UART_LCR) ; SET VALUE IN LCR
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LD A,(IY + 5) ; GET CONFIG BYTE
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BIT 5,A ; AFC REQUESTED?
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LD A,$C0 ; ASSUME AFC ON
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JR NZ,UART_INITDEV3 ; YES, IMPLEMENT IT
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XOR A ; NO AFC REQEUST, EFR := 0
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;
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UART_INITDEV3:
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UART_OUTP(UART_EFR) ; SAVE IT
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POP AF ; RECOVER ORIGINAL LCR VALUE
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UART_OUTP(UART_LCR) ; AND PUT IT BACK
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;
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UART_INITDEV4:
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#IF (UART_DEBUG)
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PRTS(" [$")
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; DEBUG: DUMP UART TYPE
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LD A,(IY + 1)
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CALL PRTHEXBYTE
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; DEBUG: DUMP IIR
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UART_INP(UART_IIR)
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CALL PC_SPACE
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CALL PRTHEXBYTE
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; DEBUG: DUMP LCR
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UART_INP(UART_LCR)
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CALL PC_SPACE
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CALL PRTHEXBYTE
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; DEBUG: DUMP MCR
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UART_INP(UART_MCR)
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CALL PC_SPACE
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CALL PRTHEXBYTE
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; DEBUG: DUMP EFR
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UART_INP(UART_LCR)
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PUSH AF
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LD A,$BF
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UART_OUTP(UART_LCR)
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UART_INP(UART_EFR)
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LD H,A
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EX (SP),HL
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LD A,H
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UART_OUTP(UART_LCR)
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POP AF
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CALL PC_SPACE
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CALL PRTHEXBYTE
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PRTC(']')
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#ENDIF
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;
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XOR A ; SIGNAL SUCCESS
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RET
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;
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;
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;
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UART_QUERY:
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LD E,(IY + 4) ; FIRST CONFIG BYTE TO E
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LD D,(IY + 5) ; SECOND CONFIG BYTE TO D
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XOR A ; SIGNAL SUCCESS
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RET ; DONE
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;
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;
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;
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UART_DEVICE:
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LD D,CIODEV_UART ; D := DEVICE TYPE
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LD E,(IY) ; E := PHYSICAL UNIT
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LD C,$00 ; C := DEVICE TYPE, 0x00 IS RS-232
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XOR A ; SIGNAL SUCCESS
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RET
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;
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; UART DETECTION ROUTINE
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;
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UART_DETECT:
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;
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; SEE IF UART IS THERE BY CHECKING DLAB FUNCTIONALITY
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XOR A ; ZERO ACCUM
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UART_OUTP(UART_IER) ; IER := 0
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LD A,$80 ; DLAB BIT ON
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UART_OUTP(UART_LCR) ; OUTPUT TO LCR (DLAB REGS NOW ACTIVE)
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LD A,$5A ; LOAD TEST VALUE
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UART_OUTP(UART_DLM) ; OUTPUT TO DLM
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UART_INP(UART_DLM) ; READ IT BACK
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CP $5A ; CHECK FOR TEST VALUE
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JP NZ,UART_DETECT_NONE ; NOPE, UNKNOWN UART OR NOT PRESENT
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XOR A ; DLAB BIT OFF
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UART_OUTP(UART_LCR) ; OUTPUT TO LCR (DLAB REGS NOW INACTIVE)
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UART_INP(UART_IER) ; READ IER
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CP $5A ; CHECK FOR TEST VALUE
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JP Z,UART_DETECT_NONE ; IF STILL $5A, UNKNOWN OR NOT PRESENT
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;
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; TEST FOR FUNCTIONAL SCRATCH REG, IF NOT, WE HAVE AN 8250
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LD A,$5A ; LOAD TEST VALUE
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UART_OUTP(UART_SCR) ; PUT IT IN SCRATCH REGISTER
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UART_INP(UART_SCR) ; READ IT BACK
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CP $5A ; CHECK IT
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JR NZ,UART_DETECT_8250 ; STUPID 8250
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;
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; TEST FOR EFR REGISTER WHICH IMPLIES 16650/850
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LD A,$BF ; VALUE TO ENABLE EFR
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UART_OUTP(UART_LCR) ; WRITE IT TO LCR
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UART_INP(UART_SCR) ; READ SCRATCH REGISTER
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CP $5A ; SPR STILL THERE?
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JR NZ,UART_DETECT1 ; NOPE, HIDDEN, MUST BE 16650/850
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;
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; RESET LCR TO DEFAULT (DLAB OFF)
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;LD A,$80 ; DLAB BIT ON
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XOR A ; DLAB BIT OFF
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UART_OUTP(UART_LCR) ; RESET LCR
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;
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; TEST FCR TO ISOLATE 16450/550/550A
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LD A,$E7 ; TEST VALUE
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UART_OUTP(UART_FCR) ; PUT IT IN FCR
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UART_INP(UART_IIR) ; READ BACK FROM IIR
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BIT 6,A ; BIT 6 IS FIFO ENABLE, LO BIT
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JR Z,UART_DETECT_16450 ; IF NOT SET, MUST BE 16450
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BIT 7,A ; BIT 7 IS FIFO ENABLE, HI BIT
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JR Z,UART_DETECT_16550 ; IF NOT SET, MUST BE 16550
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BIT 5,A ; BIT 5 IS 64 BYTE FIFO
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JR Z,UART_DETECT2 ; IF NOT SET, MUST BE 16550A/C
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JR UART_DETECT_16750 ; ONLY THING LEFT IS 16750
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;
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UART_DETECT1: ; PICK BETWEEN 16650/850
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; RESET LCR TO DEFAULT (DLAB OFF)
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XOR A ; DLAB BIT OFF
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UART_OUTP(UART_LCR) ; RESET LCR
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; NOT SURE HOW TO DIFFERENTIATE 16650 FROM 16850 YET
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JR UART_DETECT_16650 ; ASSUME 16650
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RET
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;
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UART_DETECT2: ; PICK BETWEEN 16550A/C
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; SET AFC BIT IN FCR
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LD A,$20 ; SET AFC BIT, MCR:5
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UART_OUTP(UART_MCR) ; WRITE NEW FCR VALUE
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;
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; READ IT BACK, IF SET, WE HAVE 16550C
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UART_INP(UART_MCR) ; READ BACK MCR
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BIT 5,A ; CHECK AFC BIT
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JR Z,UART_DETECT_16550A ; NOT SET, SO 16550A
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JR UART_DETECT_16550C ; IS SET, SO 16550C
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;
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UART_DETECT_NONE:
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LD A,(IY + 2) ; BASE IO PORT
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CP $68 ; IS THIS PRIMARY SBC PORT?
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JR Z,UART_DETECT_8250 ; SPECIAL CASE FOR PRIMARY UART!
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LD A,UART_NONE ; IF SO, TREAT AS 8250 NO MATTER WHAT
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RET
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;
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UART_DETECT_8250:
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LD A,UART_8250
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RET
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;
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UART_DETECT_16450:
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LD A,UART_16450
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RET
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;
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UART_DETECT_16550:
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LD A,UART_16550
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RET
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;
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UART_DETECT_16550A:
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LD A,UART_16550A
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RET
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;
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UART_DETECT_16550C:
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LD A,UART_16550C
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RET
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;
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UART_DETECT_16650:
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LD A,UART_16650
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RET
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;
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UART_DETECT_16750:
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LD A,UART_16750
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RET
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;
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UART_DETECT_16850:
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LD A,UART_16850
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RET
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;
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; COMPUTE DIVISOR TO BC
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;
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UART_COMPDIV:
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; WE WANT TO DETERMINE A DIVISOR FOR THE UART CLOCK
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; THAT RESULTS IN THE DESIRED BAUD RATE.
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; BAUD RATE = UART CLK / DIVISOR, OR TO SOLVE FOR DIVISOR
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; DIVISOR = UART CLK / BAUDRATE.
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; THE UART CLOCK IS THE UART OSC PRESCALED BY 16. ALSO, WE CAN
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; TAKE ADVANTAGE OF ENCODED BAUD RATES ALWAYS BEING A FACTOR OF 75.
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; SO, WE CAN USE (UART OSC / 16 / 75) / (BAUDRATE / 75)
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;
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; FIRST WE DECODE THE BAUDRATE, BUT WE USE A CONSTANT OF 1 INSTEAD
|
|
; OF THE NORMAL 75. THIS PRODUCES (BAUDRATE / 75).
|
|
;
|
|
LD A,D ; GET CONFIG MSB
|
|
AND $1F ; ISOLATE ENCODED BAUD RATE
|
|
LD L,A ; PUT IN L
|
|
LD H,0 ; H IS ALWAYS ZERO
|
|
LD DE,1 ; USE 1 FOR ENCODING CONSTANT
|
|
CALL DECODE ; DE:HL := BAUD RATE, ERRORS IGNORED
|
|
EX DE,HL ; DE := (BAUDRATE / 75), DISCARD HL
|
|
LD HL,UARTOSC / 16 / 75 ; HL := (UART OSC / 16 / 75)
|
|
JP DIV16 ; BC := HL/DE == DIVISOR AND RETURN
|
|
;
|
|
;
|
|
;
|
|
UART_PRTCFG:
|
|
; ANNOUNCE PORT
|
|
CALL NEWLINE ; FORMATTING
|
|
PRTS("UART$") ; FORMATTING
|
|
LD A,(IY) ; DEVICE NUM
|
|
CALL PRTDECB ; PRINT DEVICE NUM
|
|
PRTS(": IO=0x$") ; FORMATTING
|
|
LD A,(IY + 2) ; GET BASE PORT
|
|
CALL PRTHEXBYTE ; PRINT BASE PORT
|
|
|
|
; PRINT THE UART TYPE
|
|
CALL PC_SPACE ; FORMATTING
|
|
LD A,(IY + 1) ; GET UART TYPE BYTE
|
|
RLCA ; MAKE IT A WORD OFFSET
|
|
LD HL,UART_TYPE_MAP ; POINT HL TO TYPE MAP TABLE
|
|
CALL ADDHLA ; HL := ENTRY
|
|
LD E,(HL) ; DEREFERENCE
|
|
INC HL ; ...
|
|
LD D,(HL) ; ... TO GET STRING POINTER
|
|
CALL WRITESTR ; PRINT IT
|
|
;
|
|
; ALL DONE IF NO UART WAS DETECTED
|
|
LD A,(IY + 1) ; GET UART TYPE BYTE
|
|
OR A ; SET FLAGS
|
|
RET Z ; IF ZERO, NOT PRESENT
|
|
;
|
|
PRTS(" MODE=$") ; FORMATTING
|
|
LD E,(IY + 4) ; LOAD CONFIG
|
|
LD D,(IY + 5) ; ... WORD TO DE
|
|
CALL PS_PRTSC0 ; PRINT CONFIG
|
|
;
|
|
; ; PRINT FEATURES ENABLED
|
|
; LD A,(UART_FEAT)
|
|
; BIT UART_FIFO,A
|
|
; JR Z,UART_INITUNIT2
|
|
; PRTS(" FIFO$")
|
|
;UART_INITUNIT2:
|
|
; BIT UART_AFC,A
|
|
; JR Z,UART_INITUNIT3
|
|
; PRTS(" AFC$")
|
|
;UART_INITUNIT3:
|
|
;
|
|
XOR A
|
|
RET
|
|
;
|
|
; ROUTINES TO READ/WRITE PORTS INDIRECTLY
|
|
;
|
|
; READ VALUE OF UART PORT ON TOS INTO REGISTER A
|
|
;
|
|
UART_INP_IMP:
|
|
EX (SP),HL ; SWAP HL AND TOS
|
|
PUSH BC ; PRESERVE BC
|
|
LD A,(IY + 2) ; GET UART IO BASE PORT
|
|
OR (HL) ; OR IN REGISTER ID BITS
|
|
LD C,A ; C := PORT
|
|
IN A,(C) ; READ PORT INTO A
|
|
POP BC ; RESTORE BC
|
|
INC HL ; BUMP HL PAST REG ID PARM
|
|
EX (SP),HL ; SWAP BACK HL AND TOS
|
|
RET
|
|
;
|
|
; WRITE VALUE IN REGISTER A TO UART PORT ON TOS
|
|
;
|
|
UART_OUTP_IMP:
|
|
EX (SP),HL ; SWAP HL AND TOS
|
|
PUSH BC ; PRESERVE BC
|
|
LD B,A ; PUT VALUE TO WRITE IN B
|
|
LD A,(IY + 2) ; GET UART IO BASE PORT
|
|
OR (HL) ; OR IN REGISTER ID BITS
|
|
LD C,A ; C := PORT
|
|
OUT (C),B ; WRITE VALUE TO PORT
|
|
POP BC ; RESTORE BC
|
|
INC HL ; BUMP HL PAST REG ID PARM
|
|
EX (SP),HL ; SWAP BACK HL AND TOS
|
|
RET
|
|
;
|
|
;
|
|
;
|
|
UART_TYPE_MAP:
|
|
.DW UART_STR_NONE
|
|
.DW UART_STR_8250
|
|
.DW UART_STR_16450
|
|
.DW UART_STR_16550
|
|
.DW UART_STR_16550A
|
|
.DW UART_STR_16550C
|
|
.DW UART_STR_16650
|
|
.DW UART_STR_16750
|
|
.DW UART_STR_16850
|
|
|
|
UART_STR_NONE .DB "<NOT PRESENT>$"
|
|
UART_STR_8250 .DB "8250$"
|
|
UART_STR_16450 .DB "16450$"
|
|
UART_STR_16550 .DB "16550$"
|
|
UART_STR_16550A .DB "16550A$"
|
|
UART_STR_16550C .DB "16550C$"
|
|
UART_STR_16650 .DB "16650$"
|
|
UART_STR_16750 .DB "16750$"
|
|
UART_STR_16850 .DB "16850$"
|
|
;
|
|
UART_PAR_MAP .DB "NONENMNS"
|
|
;
|
|
; WORKING VARIABLES
|
|
;
|
|
UART_DEV .DB 0 ; DEVICE NUM USED DURING INIT
|
|
;
|
|
; UART PORT TABLE
|
|
;
|
|
UART_CFG:
|
|
#IF (UARTSBC)
|
|
; SBC/ZETA ONBOARD SERIAL PORT
|
|
.DB 0 ; DEVICE NUMBER (UPDATED DURING INIT)
|
|
.DB 0 ; UART TYPE
|
|
.DB $68 ; IO PORT BASE (RBR, THR)
|
|
.DB $68 + UART_LSR ; LINE STATUS PORT (LSR)
|
|
.DW UARTCFG ; LINE CONFIGURATION
|
|
.FILL 2,$FF ; FILLER
|
|
#ENDIF
|
|
#IF (UARTCAS)
|
|
; CASSETTE INTERFACE SERIAL PORT
|
|
.DB 0 ; DEVICE NUMBER (UPDATED DURING INIT)
|
|
.DB 0 ; UART TYPE
|
|
.DB $80 ; IO PORT BASE (RBR, THR)
|
|
.DB $80 + UART_LSR ; LINE STATUS PORT (LSR)
|
|
.DW UARTCASSPD ; LINE CONFIGURATION
|
|
.FILL 2,$FF ; FILLER
|
|
#ENDIF
|
|
#IF (UARTMFP)
|
|
; MF/PIC SERIAL PORT
|
|
.DB 0 ; DEVICE NUMBER (UPDATED DURING INIT)
|
|
.DB 0 ; UART TYPE
|
|
.DB $48 ; IO PORT BASE (RBR, THR)
|
|
.DB $48 + UART_LSR ; LINE STATUS PORT (LSR)
|
|
.DW UARTCFG ; LINE CONFIGURATION
|
|
.FILL 2,$FF ; FILLER
|
|
#ENDIF
|
|
#IF (UART4)
|
|
; 4UART SERIAL PORT A
|
|
.DB 0 ; DEVICE NUMBER (UPDATED DURING INIT)
|
|
.DB 0 ; UART TYPE
|
|
.DB $C0 ; IO PORT BASE (RBR, THR)
|
|
.DB $C0 + UART_LSR ; LINE STATUS PORT (LSR)
|
|
.DW UARTCFG ; LINE CONFIGURATION
|
|
.FILL 2,$FF ; FILLER
|
|
; 4UART SERIAL PORT B
|
|
.DB 0 ; DEVICE NUMBER (UPDATED DURING INIT)
|
|
.DB 0 ; UART TYPE
|
|
.DB $C8 ; IO PORT BASE (RBR, THR)
|
|
.DB $C8 + UART_LSR ; LINE STATUS PORT (LSR)
|
|
.DW UARTCFG ; LINE CONFIGURATION
|
|
.FILL 2,$FF ; FILLER
|
|
; 4UART SERIAL PORT C
|
|
.DB 0 ; DEVICE NUMBER (UPDATED DURING INIT)
|
|
.DB 0 ; UART TYPE
|
|
.DB $D0 ; IO PORT BASE (RBR, THR)
|
|
.DB $D0 + UART_LSR ; LINE STATUS PORT (LSR)
|
|
.DW UARTCFG ; LINE CONFIGURATION
|
|
.FILL 2,$FF ; FILLER
|
|
; 4UART SERIAL PORT D
|
|
.DB 0 ; DEVICE NUMBER (UPDATED DURING INIT)
|
|
.DB 0 ; UART TYPE
|
|
.DB $D8 ; IO PORT BASE (RBR, THR)
|
|
.DB $D8 + UART_LSR ; LINE STATUS PORT (LSR)
|
|
.DW UARTCFG ; LINE CONFIGURATION
|
|
.FILL 2,$FF ; FILLER
|
|
#ENDIF
|
|
#IF (UARTRC)
|
|
; UARTRC SERIAL PORT A
|
|
.DB 0 ; DEVICE NUMBER (UPDATED DURING INIT)
|
|
.DB 0 ; UART TYPE
|
|
.DB $A0 ; IO PORT BASE (RBR, THR)
|
|
.DB $A0 + UART_LSR ; LINE STATUS PORT (LSR)
|
|
.DW UARTCFG ; LINE CONFIGURATION
|
|
.FILL 2,$FF ; FILLER
|
|
; UARTRC SERIAL PORT B
|
|
.DB 0 ; DEVICE NUMBER (UPDATED DURING INIT)
|
|
.DB 0 ; UART TYPE
|
|
.DB $A8 ; IO PORT BASE (RBR, THR)
|
|
.DB $A8 + UART_LSR ; LINE STATUS PORT (LSR)
|
|
.DW UARTCFG ; LINE CONFIGURATION
|
|
.FILL 2,$FF ; FILLER
|
|
#ENDIF
|
|
;
|
|
UART_CNT .EQU ($ - UART_CFG) / 8
|
|
|