CPCLER at 20:43, 13 March 2007

2007-03-13T20:43:28Z

← Older revision		Revision as of 20:43, 13 March 2007
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	defb "Hello World!",0		defb "Hello World!",0
	</pre>		</pre>

			[[Category:Programming]]

CPCLER at 08:00, 13 March 2007

2007-03-13T08:00:02Z

New page

<pre>
;; This example shows how to access the firmware from within CP/M+.
;; This example does not work with CP/M2.2
;;
;;---------------------------------------------------------

org &100 ;; origin for C/PM .COM programs
nolist
write"test2.com"

.scr_set_mode equ &bc0e
.txt_output equ &bb5a

;;---------------------------------------------------------
;; get address of routine to call to execute
;; a firmware function

ld hl,(&0001)
ld de,&0057
add hl,de
ld (firm_jump+1),hl

;;---------------------------------------------------------
;; change the display mode to mode 1
ld a,1
call firm_jump
defw scr_set_mode

;; display a message on the screen
ld hl,test_message
call display_message

;; quit back to command-line
ret

;;---------------------------------------------------------
;; HL = pointer to null terminated message
.display_message
ld a,(hl) ;; get ASCII character
inc hl ;; increment pointer for next character
or a ;; end of message marker (0)?
ret z ;; quit if end of message marker found.

call display_char ;; send character to console output
jp display_message ;; loop for next char

;;---------------------------------------------------------
.display_char
call firm_jump
defw txt_output ;; firmware function: TXT OUTPUT
ret

;;---------------------------------------------------------
;; execute a firmware function
.firm_jump
jp 0

;;---------------------------------------------------------
.test_message
defb "Hello World!",0
</pre>

Programming:Executing firmware functions from within CP/M plus - Revision history

CPCLER at 20:43, 13 March 2007

CPCLER at 08:00, 13 March 2007