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

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1 ;******************************************************************************
2 ;* Z80 Assembler program *
3 ;* Josef Reisinger *
4 ;* josef.reisinger@htl-hl.ac.at *
5 ;* 10/07/2017 *
6 ;******************************************************************************
7
8 ; ---------------------------- PIO 82C55 I/O ---------------------------------
9 0080 PIO_A: EQU $80 ; (INPUT)
10 0081 PIO_B: EQU $81 ; (OUTPUT) OUT TO LEDS
11 0082 PIO_C: EQU $82 ; (INPUT) IN from DIP SWITCHES
12 0083 PIO_CON: EQU $83 ; CONTROL BYTE PIO 82C55
13
14 ; --------------------------- CTC Z80 Timer Counter --------------------------
15 0000 CTC0 EQU $00 ; Channel 0
16 0001 CTC1 EQU $01 ; Channel 1
17 0002 CTC2 EQU $02 ; Channel 2
18 0003 CTC3 EQU $03 ; Channel 3
19
20 ; -------------------------- SIO (USART) ----------------------------------------
21 0040 SIO_A_D: EQU $40 ; Channel A Data Register
22 0041 SIO_B_D: EQU $41 ; Channel B Data Register
23 0042 SIO_A_C: EQU $42 ; Channel A Control Register
24 0043 SIO_B_C: EQU $43 ; Channel B Control Register
25
26
27 ;-------------------------- CONSTANTS ----------------------------------------
28 FFFF RAMTOP: EQU $FFFF ; 32Kb RAM 8000H-FFFFH
29 8000 COUNTER: EQU $8000 ; RAM Counter
30
31 ;******************************************************************************
32 ;* RESET HANDLER *
33 ;* Function: Initalize system and start Main Programm *
34 ;******************************************************************************
35 0000 ORG $0000
36 0000 F3 DI ; Disable interrupt
37 0001 31 FF FF LD SP,RAMTOP ; Set stack pointer
38 0004 C3 00 01 JP MAIN ; jump to Main program
39
40
41 ;*******************************************************************
42 ;* MAIN PROGRAM *
43 ;*******************************************************************
44 0100 ORG $100
45 0100 3E 99 MAIN: LD A,$99 ; Initialize 8255: PA0-PA7=IN (DIP SWITCHES), PB0-PB7=OUT (LEDS),
46 0102 D3 83 OUT (PIO_CON),A ; PC0-PC7=IN, Mode 0 Selection
47 0104 3E 01 LD A,$01 ; Initialize RAM Counter
48 0106 21 00 80 LD HL,COUNTER ; Load RAM Counter Address
49 0109 77 LD (HL),A ; Store Counter in RAM cell
50 010A 7E AGAIN: LD A,(HL) ; Load RAM Counter
51 010B D3 81 OUT (PIO_B),A ; Output RAM Counter to LEDs (PB0-PB7)
52 010D 34 INC (HL) : Increment RAM Counter
53 010E CD 14 01 CALL _WAIT
54 0111 C3 0A 01 JP AGAIN ; Endless
55
56
57
58 ;*******************************************************************
59 ;* Warteschleife 0,5s *
60 ;*******************************************************************
61 0114 16 FF _WAIT: LD D,$FF ;
62 0116 1E FF _OUTER: LD E,$FF ;
63 0118 1D _INNER: DEC E
64 0119 C2 18 01 JP NZ,_INNER
65 011C 15 DEC D
66 011D C2 16 01 JP NZ,_OUTER
67 0120 C9 RET
68
69
70
71
72
Symbol table:
AGAIN 010A COUNTER 8000 CTC0 0000 CTC1 0001
CTC2 0002 CTC3 0003 MAIN 0100 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
_INNER 0118 _OUTER 0116 _WAIT 0114
19 symbols.