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@DanielKeep
Created April 26, 2012 12:01
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Floppy test program
You can get a pre-generated disk image here:
http://ompldr.org/vZGlzZA/hello.zip
; This program expects a disk with a zero-terminated, pre-
; formatted string at the first sector. It will read the first
; sector, display the string, add the value 42 at offset
; 0x100, then write the buffer back to the second sector.
:START sub sp, 1
; Map screen. Assuming screen = dev 0. Blame Bernard!
set a, 0
set b, 0x8000
hwi 0
; Scan hardware list for floppy device
hwn i
sub i, 1
:.query_device hwq i
ifn a, 0x4cae
set pc, .next_device
ifn b, 0x74fa
set pc, .next_device
; Found it!
set pc, .found_device
:.next_device ife i, 0
set pc, .no_floppy
sub i, 1
set pc, .query_device
:.no_floppy set a, NO_FLOPPY
jsr puts
jsr HALT
:.no_disk set a, NO_DISK
jsr puts
jsr HALT
:.read_failed set a, READ_FAILED
jsr puts
jsr HALT
:.write_failed set a, WRITE_FAILED
jsr puts
jsr HALT
:.found_device set [FLOPPY_DEVICE], i
set a, 0
hwi [FLOPPY_DEVICE]
ife b, 0
set pc, .no_disk
; Read sector 0 into memory
set a, 16
set b, 0
set c, 1
set x, 0x7000
hwi [FLOPPY_DEVICE]
ifn a, 0
set pc, .read_failed
; Print the zero-terminated string at the start of the
; sector to screen.
set a, 0x7000
jsr putsf
; Write 42 to offset 0x0100 and write back to sector 1.
set a, 0x7100
set [a], 42
set a, 17
set b, 1
set c, 1
set x, 0x7000
hwi [FLOPPY_DEVICE]
ifn a, 0
set pc, .write_failed
jsr HALT
:puts set i, [.OFFSET]
set j, a
:.next ife [j], 0
set pc, .end
set [i], [j]
bor [i], 0xF000
add i, 1
add j, 1
set pc, .next
:.end set [.OFFSET], i
set pc, pop
:.OFFSET dat 0x8000
:putsf set i, [puts.OFFSET]
set j, a
:.next ife [j], 0
set pc, .end
set [i], [j]
; bor [i], 0xF000
add i, 1
add j, 1
set pc, .next
:.end set [puts.OFFSET], i
set pc, pop
:HALT sub pc, 1
:FLOPPY_DEVICE dat 0
:NO_FLOPPY dat "No floppy drive!", 0
:NO_DISK dat "No disk inserted!", 0
:READ_FAILED dat "Read failed :'(", 0
:WRITE_FAILED dat "Write failed :'(", 0
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