-
Notifications
You must be signed in to change notification settings - Fork 1
/
test.dasm
126 lines (102 loc) · 1.57 KB
/
test.dasm
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
;include(`forth_macros.m4')
;call an interrupt
IAS int-handler
INT 0x08
;use a variable
JSR find-clock
;turn on the clock
SET A, 0
SET B, 90
HWI [clock-hw]
;turn on the screen
JSR find-screen
SET A, 0
SET B, [screen-mem-loc]
HWI [screen-hw]
;find the keyboard
JSR find-keyboard
SET A, 3
SET B, 0x01
HWI [keyboard-hw]
SET A, 0
SET B, 0x00
HWI [keyboard-hw]
;Encode the character B
SET A, 66
JSR generate-char
SET B, [screen-mem-loc]
SET [B], A
SET A, 67
JSR generate-char
SET B, [screen-mem-loc]
ADD B, 1
SET [B], A
SET X, 5
SET Y, 5
SET A, greeting
SET B, [screen-mem-loc]
JSR print-string
JSR tick-wait
;Do some signed math
SET A, -1
SET B, 5
MLI B, A
SET X, 1
SET Y, 5
MLI Y, X
SET PC, end
;echo the key in C to the memory loc
; [screen-cur-pos], then increment that loc
:echo-key
SET PUSH, A
SET PUSH, B
SET A, C
JSR generate-char
SET B, [screen-cur-pos]
SET [B], A
ADD [screen-cur-pos], 1
SET B, POP
SET A, POP
SET PC, POP
; end echo-key
;handle a keypress
:key-handler
SET PUSH, A
SET PUSH, B
SET PUSH, C
;get the key
:key-handle-loop
SET A, 0x01
HWI [keyboard-hw]
IFE C, 0x0
SET PC, key-handle-end
IFE C, 0x10
SET PC, key-handle-backspace
JSR echo-key
SET PC, key-handle-loop
:key-handle-backspace
SET PUSH, B
SUB [screen-cur-pos], 1
SUB B, [screen-cur-pos]
SET [B], 0x0000
SET B, POP
SET PC, key-handle-loop
:key-handle-end
SET C, PUSH
SET B, POP
SET A, POP
SET PC, POP
;end key-handler
; interrupt handler
:int-handler
IFE A, 0x01
JSR key-handler
RFI 0
#include util.dasm
:screen-mem-loc
dat 0xB800
:screen-cur-pos
dat 0xB800
:greeting
dat "Hello, world!"
:end