;
;
; Here is an interesting "patch" to Digital Research's
; STAT.COM, that incorporates a "real time clock display. This
; patch works with STAT.COM for CP/M version 2.2 ONLY. Merge
; it into STAT.COM as follows:
;
; A>DDT STAT.COM<cr>
; NEXT PC
; 1580 0100
; -ISTATTIME.HEX<cr>
; -R<cr>
; NEXT PC
; 16CD 0000
; -^C
; A>SAVE 22 STATTIME.COM<cr>
;
; Now you have a new "STAT" command file called STATTIME.COM,
; and it will display the "real time" on every execution...
;
; Best regards,
;
; Kelly Smith, MP/M-Net (tm) Sysop
; (805) 527-9321 (Modem, 300 Baud)
;
;
;
; STATTIME.ASM (revised 10/16/80)
;
; Revised from the May 1980, INTERFACE AGE MAGAZINE
;
; For Compu-Time T-102 TIME/DATE board (With MM 5375 AC)
;
; or,
;
; QT Computer Systems Inc. "Clock/Calendar +" board
;
;
bdos equ 5
pbuf equ 9
clock equ 080h ; real time clock base port address
endif
if ct
clock equ 024h ; real time clock base port address
endif
org 0100h
jmp date
org 1501h ; version 2.2 stat.com entry address
date: push psw ! push b ! push d ! push h
lxi h,month ; point to month
mvi d,8 ; select month tens digit
call digit ; read and store high digit
rlc ! rlc ! rlc ! rlc ; shift to high order hex digit
mov b,a ; save in b reg.
call digit ; read and store month units digit
ora b ; or-in the units and tens digit
mov b,a ; save the month in b reg.
call digit ; read and store the day tens digit
rlc ! rlc ! rlc ! rlc ; shift to high order hex digit
mov c,a ; save in c reg.
call digit ; read and store day units digit
ora c ; or-in the units and tens digit
mov c,a ; save the day in c reg.
;
; test the date, and convert it to four year calendar format
;
cpi 031h ; 31st day?
mov a,b ; get the month, for next test
jnz m2 ; if not the 31st, test for february
cpi 2 ; test for months < 31 days
jz fix ; ...and fix if needed
cpi 4
jz fix
cpi 6
jz fix
cpi 9
jz fix
cpi 011h
jz fix
m2: cpi 2 ; test for february
jnz time ; if not february, then read time
mov a,c ; get day for test
cpi 029h ; is this the 29th day?
;
; insert two NOP's over previous instruction, if this is a leap year
;
jz fix ; fix date...
cpi 030h ; 30th day?
jnz time ; if not the 29th or 30th, go read time
fix: mvi a,41 ; select month units and fast set
call rdigit ; read the month units digit
mov b,a ; save in b reg.
floop: in clock ; read the months unit digit
cmp b ; test for digit changed
jz floop ; wait until month is bumped (stable data)
time: lxi h,hour ; point to hour
mvi d,0 ; select hour tens digit
call ddigit ; read hour tens and units
inx h ; step over ":"
call ddigit ; read minutes tens and units
inx h ; step over ":"
call ddigit ; read second tens and units
lxi d,pdate ; point to date and time message
mvi c,pbuf ; print buffer function
call bdos ; let CP/M do the work...
lda month ; get high byte of the month
cpi ' ' ; in the range of january to september?
jz jansept
lda month+1 ; must be october to december...
cpi '0' ; october?
lxi d,oct
jz pmonth ; print, if so
cpi '1' ; november?
lxi d,nov
jz pmonth ; print, if so
lxi d,dec ; december.
jmp pmonth ; print it...
jansept:lda month+1 ; it's january to september
cpi '1' ; january?
lxi d,jan
jz pmonth ; print, if so
cpi '2' ; february?
lxi d,feb
jz pmonth ; print, if so
cpi '3' ; march?
lxi d,mar
jz pmonth ; print, if so
cpi '4' ; april?
lxi d,apr
jz pmonth ; print, if so
cpi '5' ; may?
lxi d,may
jz pmonth ; print, if so
cpi '6' ; june?
lxi d,jun
jz pmonth ; print month
cpi '7' ; july?
lxi d,jul
jz pmonth ; print, if so
cpi '8' ; august?
lxi d,aug
jz pmonth ; print, if so
lxi d,sep ; it's september
pmonth: mvi c,pbuf ; print buffer function
call bdos ; let CP/M do the work...
done: lxi d,day ; get the day
mvi c,pbuf ; print buffer function
call bdos ; let CP/M do the work...
pop h ! pop d ! pop b ! pop psw
jmp stat ; now jump into STAT...
ddigit: call digit ; read and store two digits
digit: mov a,d ; move digit select code to a reg.
call rdigit ; read a clock digit
cpi 0ffh ; test for board present
jz nobrd ; go print error message
ori 030h ; convert digit to ASCII
cpi 03fh ; test for blanked leading zero
jnz store ; go store digit, if not blanked
mvi a,020h ; convert to a blank
store: mov m,a ; store the digit in message buffer
inx h ; bump message pointer buffer location
inr d ; step to next digit
ani 00fh ; mask off high ASCII nibble
ret ; return with digit in a reg.
nobrd: pop h ; adjust the stack
lxi d,errmsg; point to the error message
jmp done ; print error message, and exit to CP/M
rdigit: out clock ; select digit
mvi a,0 ; ...some delay time for settling
dloop: dcr a
jnz dloop
in clock ; read a digit
ret ; return with digit in a reg.
;
; message buffers
;
pdate: db cr,lf,'Date: $'
month: ds 2 ; the month
day: db 'xx, ' ; the day...
db '1980' ; the year...
db ' Time: '
hour: db 'xx:' ; the hour...
db 'xx:' ; the minute...
db 'xx' ; the second...
db cr,lf,'$' ; string delimeter
errmsg: db cr,lf,'The Clock Board is NOT INSTALLED!',cr,lf,'$'
jan: db 'January $'
feb: db 'February $'
mar: db 'March $'
apr: db 'April $'
may: db 'May $'
jun: db 'June $'
jul: db 'July $'
Aug: db 'August $'
sep: db 'September $'
oct: db 'October $'
nov: db 'November $'
dec: db 'December $'
