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Updated for extra ram and external keyboard support

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Dreaded_X 2020-10-01 21:35:36 +02:00
parent 0831441a8a
commit 59f802bc9f
8 changed files with 48 additions and 48 deletions
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bin/s.com Normal file
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36
src/MONITOR.z80
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@ -6,12 +6,12 @@
;Assumes memory configuration is all-RAM
;
;The subroutines use these variables in RAM, same area as ROM monitor:
current_location: equ 0x7100 ;word variable in RAM
line_count: equ 0x7102 ;byte variable in RAM
byte_count: equ 0x7103 ;byte variable in RAM
value_pointer: equ 0x7104 ;word variable in RAM
current_value: equ 0x7106 ;word variable in RAM
buffer: equ 0x7108 ;buffer in RAM -- up to stack area
current_location: equ 0xE100 ;word variable in RAM
line_count: equ 0xE102 ;byte variable in RAM
byte_count: equ 0xE103 ;byte variable in RAM
value_pointer: equ 0xE104 ;word variable in RAM
current_value: equ 0xE106 ;word variable in RAM
buffer: equ 0xE108 ;buffer in RAM -- up to stack area
;Will use stack of calling program (CP/M) which is re-initialized at re-boot.
;
;
@ -21,12 +21,12 @@ buffer: equ 0x7108 ;buffer in RAM -- up to stack area
#code BOOT, 0x0100
ld hl,code_origin ;start of code to transfer
ld bc,code_end-code_start+1 ;length of code to transfer
ld de,07200h ;target of transfer
ld de,0E200h ;target of transfer
ldir ;Z80 transfer instruction
jp 07200h
jp 0E200h
code_origin: ;address of first byte of code before transfer
;
#code MAIN, 0x7200
#code MAIN, 0xE200
code_start: jp monitor_start
;
;Puts a single char (byte value) on serial output
@ -54,10 +54,10 @@ write_string: in a,(3) ;read status
;
;Binary loader. Receive a binary file, place in memory.
;Address of load passed in HL, length of load (= file length) in BC
bload: in a,(3) ;get status
and 002h ;check RxRDY bit
bload: in a,(0x1F) ;get status
and 001h ;check RxRDY bit
jp z,bload ;not ready, loop
in a,(2)
in a,(0x1E)
ld (hl),a
inc hl
dec bc ;byte counter
@ -91,10 +91,10 @@ get_line: ld c,000h ;line position
ld d,a ;after this don't need to preserve hl
ld a,l ;subroutines called don't use de
ld e,a
get_line_next_char: in a,(3) ;get status
and 002h ;check RxRDY bit
get_line_next_char: in a,(0x1F) ;get status
and 001h ;check RxRDY bit
jp z,get_line_next_char ;not ready, loop
in a,(2) ;get char
in a,(0x1E) ;get char
cp 00dh ;check if return
ret z ;yes, normal exit
cp 07fh ;check if backspace (VT102 keys)
@ -378,10 +378,10 @@ load_done: call write_newline
;
;Get one ASCII character from the serial port.
;Returns with char in A reg. No error checking.
get_char: in a,(3) ;get status
and 002h ;check RxRDY bit
get_char: in a,(0x1F) ;get status
and 001h ;check RxRDY bit
jp z,get_char ;not ready, loop
in a,(2) ;get char
in a,(0x1E) ;get char
ret
;
;Subroutine to start a new line

16
src/bios.z80
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@ -1,8 +1,8 @@
; skeletal cbios for first level of CP/M 2.0 alteration
;
ccp: equ 6400h ;base of ccp
bdos: equ 6C06h ;bdos entry
bios: equ 7A00h ;base of bios
ccp: equ 0E400h ;base of ccp
bdos: equ 0EC06h ;bdos entry
bios: equ 0FA00h ;base of bios
cdisk: equ 0004h ;address of current disk number 0=a,... l5=p
iobyte: equ 0003h ;intel i/o byte
disks: equ 04h ;number of disks in the system
@ -180,8 +180,8 @@ diskok: LD c, a ;send to the ccp
; to insert your own code
;
const: ;console status, return 0ffh if character ready, 00h if not
in a,(3) ;get status
and 002h ;check RxRDY bit
in a,(0x1F) ;get status
and 001h ;check RxRDY bit
jp z,no_char
ld a,0ffh ;char ready
ret
@ -189,10 +189,10 @@ no_char:ld a,00h ;no char
ret
;
conin: ;console character into register a
in a,(3) ;get status
and 002h ;check RxRDY bit
in a,(0x1F) ;get status
and 001h ;check RxRDY bit
jp z,conin ;loop until char ready
in a,(2) ;get char
in a,(0x1E) ;get char
AND 7fh ;strip parity bit
ret
;

2
src/cpm22.z80
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@ -11,7 +11,7 @@
; Set memory limit here. This is the amount of contigeous
; ram starting from 0000. CP/M will reside at the end of this space.
;
MEM EQU 32 ;for a 62k system (TS802 TEST - WORKS OK).
MEM EQU 64 ;for a 62k system (TS802 TEST - WORKS OK).
;
IOBYTE EQU 3 ;i/o definition byte.
TDRIVE EQU 4 ;current drive name and user number.

4
src/loader.z80
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@ -8,13 +8,13 @@
hstbuf equ 0x1200 ;will put 256-byte raw sector here
disk_read equ 0x0296 ;subroutine in 2K ROM
cpm equ 0x7A00 ;CP/M cold start entry in BIOS
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,0x6400 ; Memory address -- start of CCP
ld hl,0xE400 ; Memory address -- start of CCP
loop:
call disk_read ;subroutine in ROM

2
src/putsys.z80
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@ -6,7 +6,7 @@
#target bin
#code _HOME, 0x1400
_bios equ 0x7A00
_bios equ (0x4A00+0xB000)
seldsk equ _bios+0x1b
settrk equ _bios+0x1e
setsec equ _bios+0x21

18
src/ram_monitor.z80
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@ -43,10 +43,10 @@ write_string: in a,(3) ;read status
;
;Binary loader. Receive a binary file, place in memory.
;Address of load passed in HL, length of load (= file length) in BC
bload: in a,(3) ;get status
and 002h ;check RxRDY bit
bload: in a,(0x1F) ;get status
and 001h ;check RxRDY bit
jp z,bload ;not ready, loop
in a,(2)
in a,(0x1E)
ld (hl),a
inc hl
dec bc ;byte counter
@ -80,10 +80,10 @@ get_line: ld c,000h ;line position
ld d,a ;after this don't need to preserve hl
ld a,l ;subroutines called don't use de
ld e,a
get_line_next_char: in a,(3) ;get status
and 002h ;check RxRDY bit
get_line_next_char: in a,(0x1F) ;get status
and 001h ;check RxRDY bit
jp z,get_line_next_char ;not ready, loop
in a,(2) ;get char
in a,(0x1E) ;get char
cp 00dh ;check if return
ret z ;yes, normal exit
cp 07fh ;check if backspace (VT102 keys)
@ -367,10 +367,10 @@ load_done: call write_newline
;
;Get one ASCII character from the serial port.
;Returns with char in A reg. No error checking.
get_char: in a,(3) ;get status
and 002h ;check RxRDY bit
get_char: in a,(0x1F) ;get status
and 001h ;check RxRDY bit
jp z,get_char ;not ready, loop
in a,(2) ;get char
in a,(0x1E) ;get char
ret
;
;Subroutine to start a new line

18
src/rom_monitor.z80
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@ -57,10 +57,10 @@ write_string: in a,(3) ;read status
;
;Binary loader. Receive a binary file, place in memory.
;Address of load passed in HL, length of load (= file length) in BC
bload: in a,(3) ;get status
and 002h ;check RxRDY bit
bload: in a,(0x1F) ;get status
and 001h ;check RxRDY bit
jp z,bload ;not ready, loop
in a,(2)
in a,(0x1E)
ld (hl),a
inc hl
dec bc ;byte counter
@ -94,10 +94,10 @@ get_line: ld c,000h ;line position
ld d,a ;after this don't need to preserve hl
ld a,l ;subroutines called don't use de
ld e,a
get_line_next_char: in a,(3) ;get status
and 002h ;check RxRDY bit
get_line_next_char: in a,(0x1F) ;get status
and 001h ;check RxRDY bit
jp z,get_line_next_char ;not ready, loop
in a,(2) ;get char
in a,(0x1E) ;get char
cp 00dh ;check if return
ret z ;yes, normal exit
cp 07fh ;check if backspace (VT102 keys)
@ -381,10 +381,10 @@ load_done: call write_newline
;
;Get one ASCII character from the serial port.
;Returns with char in A reg. No error checking.
get_char: in a,(3) ;get status
and 002h ;check RxRDY bit
get_char: in a,(0x1F) ;get status
and 001h ;check RxRDY bit
jp z,get_char ;not ready, loop
in a,(2) ;get char
in a,(0x1E) ;get char
ret
;
;Subroutine to start a new line