IBM 5150 - Page 128

LOC OBJ
LINE SOURCE
3.3
ROS CHECKSUM TEST I
3.4 J DESCRIPTION
3.5
A CHECKSUM IS DOHE FOR THE 8K RDS ttODULE
36.
CONTAINING POO AHI) BIOS.
367
;--------------------------------------------------------
EOAE
368 CI0:
369
; ZERO IN AL ALREADY
EOAE £6AO 370
OUT OAOH,Al ; DISABLE HHI INTERRUPTS
~
EOBO E683
371
OUT 83H,Al ; INITIAlZE DHA PAGE REG
E082 BA0803
372
MOV eX
,
3DSH
fOBS EE 373
OUT
OX.Al I DISABLE COLOR VIDEO
E086
FEeD
374
INC Al
fOBS 8288 375
I10V
OL,OBSH
EOBA EE
37.
OUT
OX,Al
; DISABLE BIW VIDEO, EN HIGH RES
fOBS 8099
377
MeV Al.99H
I SET 8255 A,t-INPUT ,S-OUTPUT
EoeD
E663 378
OUT
CHO_PORT .Al I WRITE 8255 tHO/MODE REG
E06F BOFt
379
MeV AL,OFCH ; DISABLE PARITY CHECKERS AND
fOCI E661
380
OUT PORT_B,Al
,
GATE SNS S~S.CASS MOTOR OFF
EOC3 8CC8 381
MeV Ax.es I SETUP S5 SEG REG
EatS 8EOO
38.
"OV
55,AX
EOC7 8E08
383 MOV
OS.AX • SET UP DATA SEG TO POINT TO
.. 4
I
ROH ADDRESS
385 ASSUME SS:COOE
EOC9 B7EO
38.
MaV
BH,OEOH
J SETtJP STARTING ROS AODR
(EOOOO J
EOCB BC16EO
387
MOV
SP,OFFSET Cl ; SETUP RE11.JRN ADDRESS
EOCE E97BOB
388
J"P
ROS_CHECKSUM
E001
389
Cll:
EOOI 750A
390
IN'
ERROl ; HALT SYSTEM IF ERROR
391 1----------------------------------------------------------------
39. 8237 OMA INITIAlIZATION CHANNEl REGISTER TEST
393 I DESCRIPTION
394 DISABLE THE 8237 OMA CONTROLLER.
VERIFY THAT TIMER 1
395
FUNCTIONS OK. WRITE/READ THE CUPR'ENT ADDRESS ANO WORD
39.
COl.tIT REGISTERS FOR All CHAWHElS. INITIALIZE AND
397
START OMA FOR MEMORY REFRESH.
398
1------------------------------------- ---- ------------- ---- -- -- --
EOD3 8004
399
MOV AL,04 ; DISABLE OHA CONTROllER
EOD5
E608 400
OUT OMA08,AL
~
401
4"
; ----- VERIFY THAT TIMER 1 FlNCTIONS OK
403
E007 8054 404
I10V AL.54H I SEL TIMER l,lSB.HOOE 2
EOD9 E643
405
OUT TIMER+3,Al
EODB 8ACI
40.
tlDV AL,CL I SET INITIAL TIMER CNT TO 0
EODO E641 407
OUT
TIMER+1,AL
EODF 408 Cl,:
i TIMERl_BITS_ON
EODF B040
40.
"OV
AL.40H
I LATCH TIMER 1 COlNT
EOEI E643
410
OUT TIMER+3,Al
Eon 80F8FF
4" C"P
Bl.OFFH
I YES - SEE IF AlL BITS GO OFF
EOE6 7407
41.
J'
C13
; TIMER I_BITS_OFF
EOE8 E441
4"
IN
AL.TIMER+l
I READ TIMER 1 COlNT
EOEA OAD8
414
OR Bl,Al
; AlL BITS ON IN TIMER
EOEC E2Ft
415
lOOP
CI'
I TIMER CBlTS_ON
...
EOEE F4
HlT
1 TIMER 1 FAILURE, HALT SYS
EOEF
417
en:
; TIMERl_SITS_OFF
EOEF 8AC3
418
Al,Sl
"OV ; SET TIMER 1 CNT
EOFt 28C9
419
SUB CX,CX
Eon E641
4'0
OUT
TIMER+l.AL
EOF5 4.,
C14:
; TIMER_LOOP
EOFS B040
4"
MOV AL,40H
I lATCH TIMER 1 COUNT
Eon E643
4"
OUT
TIMER+3.Al
EOF9 90
"4
NOP
I DelAY FOR TIMER
EOFA 90
425
NOP
EOFB E441
4 ••
IN
Al, TIMER+l i READ TIMER 1 COUNT
EOFO 2208
4'7
'NO
BL,Al
EOFF 7403
428
JZ
CIS I GO TO WRAP _DHA_REG
EIOI E,F2
429
lOOP
CI4
i TIMER_LOOP
EI03 F4 430
HlT
; TIMER ERROR - HALT SYSTEM
~
431
432
;----- INITIALIZE TIMER 1 TO REFRESH MEMORY
4"
EI04
"4
CIS:
; WRAP _DHA_REG
EI04 BOl,
435
NOV ALol8
I SETUP DIVISOR FOR REfRESH
E106 E641
436
OUT TIMER+I.Al
; WRITE TIMER 1 CNT REG
EI08 E60D
4"
OUT OMA+ODH.AL
; SEtil HASTER CLEAR TO OHA
438
System BIOS 5-35