System information

;
rstart:
lxi sp,stack; ;in case of call to mon80
; clear disk status
in rtype
in rbyte
; check if boot switch is off
coldstart:
in bsw
ani 02h ;switch on?
jnz coldstart
; clear the controller
out reset ;logic cleared
;
;
mvi b,ntrks ;number of tracks to read
lxi h,iopbo
;
start:
;
; read first/next track into cpmb
mov a,l
out ilow
mov a,h
out ihigh
waito: in dstat
ani 4
jz waito
;
; check disk status
in rtype
ani 11b
cpi 2
;
if testing
cnc rmon80 ;go to monitor if 11 or 10
endif
if not testing
jnc rstart ;retry the load
endif
;
in rbyte ;i/o complete, check status
; if not ready, then go to mon80
ral
cc rmon80 ;not ready bit set
Appendix D : MDS-800 Cold Start Loader CP/M Operating System Manual
D-2