Specifications

Application Examples
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;* *
;* SYSTEM EQUATES *
;* *
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; EQU 0 ; SET TO 0 FOR STD DOS SYSTEM
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; * ZT 8809A 8259A REGISTER EQUATES BY PORT ADDRESS *
;
; REG A ICW,OCW2,OCW3,IRR,ISR,IL
PORT_A_8809A EQU 0020H ; PORT A
ICW1_8809A EQU 00010001B ; EDGE, CASCADE, ICW4 NEEDED
OCW2_8809A EQU 01100010B ; SPECIFIC EOI FOR IR2
;
; REG B ICW2,3,4,OCW1,IMR
PORT_B_8809A EQU 0021H ; PORT B
ICW2_8809A EQU 00001000B ; TYPES 8-15D
ICW3_8809A EQU 00000100B ; SLAVE ON IR2
ICW4_8809A EQU 00011101B ; 8088, NORM EOI, BUF MASTER
OCW1_8809A EQU 00000000B ; ENABLE ALL INTERRUPTS FOR
; STD DOS
;
; * ZT 8840 8259A REGISTER EQUATES BY PORT ADDRESS *
;
; REG A ICW,OCW2,OCW3,IRR,ISR,IL
PORT_A_8840 EQU 0E7H ; PORT A
ICW1_8840 EQU 00010001B ; EDGE, CASCADE, ICW4 NEEDED
OCW2_8840 EQU 01100000B ; SPECIFIC EOI FOR IR0
;
; REG B ICW2,3,4,OCW1,IMR
PORT_B_8840 EQU 0EFH ; PORT B
ICW2_8840 EQU 11111000B ; TYPES 248-255D
ICW3_8840 EQU 00000010B ; SLAVE ID #2
ICW4_8840 EQU 00011001B ; 8088, NORM EOI, BUF SLAVE
OCW1_8840 EQU 11111110B ; ENABLE IR0 ONLY
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; * ZT 8809A PRINTER PORT REGISTER EQUATES BY PORT ADDRESS *
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PRTR_DATA EQU 0378H ; PRINTER DATA PORT
PRTR_STAT EQU 0379H ; PRINTER STATUS PORT
PRTR_CTRL EQU 037AH ; PRINTER CONTROL PORT
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; * ZT 8840 UART REGISTER EQUATES BY PORT ADDRESS *
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BASE EQU 00E0H ; FACTORY DEFAULT
UART1 EQU BASE+00H ; UART 1 ADDRESS
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; * ZT 8840 8250 REGISTER EQUATES BY PORT ADDRESS *
;
; REG #0 RECV./TRANS REG (R/W)
PORT_REC50 EQU 000H ; RECV REGISTER
PORT_XMT50 EQU 000H ; TRANS. REGISTER
PORT_DLALB EQU 000H ; IF DLAB=1, LSB DIV.
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