AMTS/Reischl/lst/pio.lst
2018-04-03 21:45:17 +02:00

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1 ;******************************************************************************
2 ;* Z80 Assemblerprogramm *
3 ;* Josef Reisinger *
4 ;* josef.reisinger@htl-hl.ac.at *
5 ;* 26/04/2015 *
6 ;******************************************************************************
7
8
9 ; ---------------------------- PIO 82C55 I/O ---------------------------------
10 0080 PIO_A: EQU $80 ; (INPUT)
11 0081 PIO_B: EQU $81 ; (OUTPUT) OUT TO LEDS
12 0082 PIO_C: EQU $82 ; (INPUT) IN from DIP SWITCHES
13 0083 PIO_CON: EQU $83 ; CONTROL BYTE PIO 82C55
14
15 ; --------------------------- CTC Z80 Timer Counter --------------------------
16 0000 CTC0 EQU $00 ; Channel 0
17 0001 CTC1 EQU $01 ; Channel 1
18 0002 CTC2 EQU $02 ; Channel 2
19 0003 CTC3 EQU $03 ; Channel 3
20
21 ; -------------------------- SIO (USART) ----------------------------------------
22 0040 SIO_A_D: EQU $40 ; Channel A Data Register
23 0041 SIO_B_D: EQU $41 ; Channel B Data Register
24 0042 SIO_A_C: EQU $42 ; Channel A Control Register
25 0043 SIO_B_C: EQU $43 ; Channel B Control Register
26
27
28 ;-------------------------- CONSTANTS ----------------------------------------
29 FFFF RAMTOP: EQU $FFFF ; 32Kb RAM 8000H-FFFFH
30
31
32 ;******************************************************************************
33 ;* START AFTER RESET, *
34 ;* Function....: ready system and restart *
35 ;******************************************************************************
36 0000 ORG $0000
37 0000 F3 DI ; Disable interrupt
38 0001 31 FF FF LD SP,RAMTOP ; Set stack pointer to top off ram
39 0004 3E 99 LD A,$99 ; PA0-PA7=IN (DIP SWITCHES), PB0-PB7=OUT (LEDS), PC0-PC7=IN, Mode 0 Selektion
40 0006 D3 83 OUT (PIO_CON),A
41 0008 DB 83 IN A,(PIO_CON)
42 000A DB 80 AGAIN: IN A,(PIO_A) ; Read actual status of Switches (PA0-PA7)
43 000C D3 81 OUT (PIO_B),A ; Output Status to LEDs (PB0-PB7)
44 000E C3 0A 00 JP AGAIN ; Endless
45
46
47
Symbol table:
AGAIN 000A CTC0 0000 CTC1 0001 CTC2 0002
CTC3 0003 PIO_A 0080 PIO_B 0081 PIO_C 0082
PIO_CON 0083 RAMTOP FFFF SIO_A_C 0042 SIO_A_D 0040
SIO_B_C 0043 SIO_B_D 0041
14 symbols