User`s guide

print:
;print the buffer addressed by de Until $
0231 D5 push d
0232 CD1502 call crlf
0235 Dl pop d ;new line
0236 0E09 mvi c,pstring
0238 CD0so0 call bdos ;print the String
023b C9 ret
readcom:
;iread the next command line to the conbuf
023C 11D102 lxi d,Prompt
023F CD3102 call print ;command?
0242 0E0a mvi c,rstring
0244 11F102 lxi d,conbuf
0247 CD0500 call bdos ;read command line
; command line iS present, scan it
024a 0E00 mvi c,0 ;Start With 00
024C 210000 lxi h,0 ; 0000
024F 11F302 lxi d,c0nlin;icommand line
0252 la readc: idax d ;inext command character
0253 13 inx d ;ito next command Position
0254 b7 ora a ;cannot be end of command
0255 C8 rz
; not zero, numeric?
0256 D630 sui '0'
0258 FE0a cpi 10 +;icarry if numeric
025a D27902 jnc endrd
4-17
4.3 A Sample Random Access Program CP/M 3 Programmer's Guide