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Split from cpm repository

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Dreaded_X 2021-01-14 02:46:09 +01:00
commit eeb7a64290
4 changed files with 103 additions and 0 deletions
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BIN
.build/loader.bin Normal file
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.build/loader.lst Normal file
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; --------------------------------------
; zasm: assemble "loader.z80"
; date: 2021-01-14 02:43:53
; --------------------------------------
;Retrieves CP/M from disk and loads it in memory starting at E400h
;Uses calls to ROM subroutine for disk read.
;Reads track 0, sectors 2 to 26, then track 1, sectors 1 to 25
;This program is loaded into LBA sector 0 of disk, read to loc. 0800h by ROM disk_read subroutine, and executed.
#target bin
#code _HOME, 0x1100
hstbuf equ 0x1200 ;will put 256-byte raw sector here
disk_read equ 0x0296 ;subroutine in 2K ROM
cpm equ 0xFA00 ;CP/M cold start entry in BIOS
main:
ld c,1 ;LBA bits 0 to 7
ld b,0 ;LBA bits 8 to 15
ld e,0 ;LBA bits 16 to 23
ld hl,0xE400 ; Memory address -- start of CCP
loop:
call disk_read ;subroutine in ROM
ld a,c
cp 50
jp z,done
inc a
ld c,a
jp loop
done:
out (1),a ;switch memory config to all-RAM
jp cpm ;to BIOS cold start entry
; +++ segments +++
#CODE _HOME = $1100 = 4352, size = $001C = 28
; +++ global symbols +++
_HOME = $1100 = 4352 _HOME loader.z80:6 (unused)
_HOME_end = $111C = 4380 _HOME loader.z80:6 (unused)
_HOME_size = $001C = 28 _HOME loader.z80:6 (unused)
cpm = $FA00 = 64000 _HOME loader.z80:11
disk_read = $0296 = 662 _HOME loader.z80:10
done = $1117 = 4375 _HOME loader.z80:28
hstbuf = $1200 = 4608 _HOME loader.z80:9 (unused)
loop = $1109 = 4361 _HOME loader.z80:19
main = $1100 = 4352 _HOME loader.z80:13 (unused)
total time: 0.0002 sec.
no errors

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Makefile Normal file
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BUILDDIR=.build
_BIN= loader.bin
BIN = $(patsubst %,$(BUILDDIR)/%,$(_BIN))
.PHONY: all clean
all: $(BUILDDIR) $(BIN)
$(BUILDDIR)/%.bin: src/%.z80 | $(BUILDDIR)
@zasm -w -i $< -o $@
$(BUILDDIR):
@mkdir $(BUILDDIR)
clean:
@rm -df $(BUILDDIR)/*.bin $(BUILDDIR)/*.lst .build

30
src/loader.z80 Normal file
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;Retrieves CP/M from disk and loads it in memory starting at E400h
;Uses calls to ROM subroutine for disk read.
;Reads track 0, sectors 2 to 26, then track 1, sectors 1 to 25
;This program is loaded into LBA sector 0 of disk, read to loc. 0800h by ROM disk_read subroutine, and executed.
#target bin
#code _HOME, 0x1100
hstbuf equ 0x1200 ;will put 256-byte raw sector here
disk_read equ 0x0296 ;subroutine in 2K ROM
cpm equ 0xFA00 ;CP/M cold start entry in BIOS
main:
ld c,1 ;LBA bits 0 to 7
ld b,0 ;LBA bits 8 to 15
ld e,0 ;LBA bits 16 to 23
ld hl,0xE400 ; Memory address -- start of CCP
loop:
call disk_read ;subroutine in ROM
ld a,c
cp 50
jp z,done
inc a
ld c,a
jp loop
done:
out (1),a ;switch memory config to all-RAM
jp cpm ;to BIOS cold start entry