The Test Box is a primitive VGA controller that uses a µController and runs at
4 MHz. The µController outputs VGA signals; the monitor receives them &
displays what is sent.
Questions & Comments?
The Test Box is a primitive VGA controller that uses a µController and runs at
4 MHz. The µController outputs VGA signals; the monitor receives them &
displays what is sent.
Code: Select all
x9:
blank ; 1
blank ; 2
blank ; 3
blank ; 4
blank ; 5
blank ; 6
blank ; 7
point ; 8 *
point ; 9 *
blank ; 10
blank ; 11
blank ; 12
blank ; 13
blank ; 14
point ; 15 *
point ; 16 *
blank ; 17
blank ; 18
blank ; 19
blank ; 20
blank ; 21
blank ; 22
blank ; 23
blank ; 24
blank ; 25
blank ; 26
HSync ; 27-29
decfsz tri9 ; 30
goto x9 ; 31
Code: Select all
x9:
blank ; 0.2 uS --DATA--
blank ; 0.4 uS
blank ; 0.6 uS
blank ; 0.8 uS
blank ; 1 uS
blank ; 1.2 uS
blank ; 1.4 uS
point ; 1.6 uS *
point ; 1.8 uS *
blank ; 2 uS
blank ; 2.2 uS
blank ; 2.4 uS
blank ; 2.6 uS
blank ; 2.8 uS
point ; 3 uS *
point ; 3.2 uS *
blank ; 3.4 uS
blank ; 3.6 uS
blank ; 3.8 uS
blank ; 4 uS
blank ; 4.2 uS
blank ; 4.4 uS
.....
.....
.....
blank ; 24.4 uS
blank ; 24.6 uS
blank ; 24.8 uS
blank ; 25 uS
nop ; 25.2 uS --Blank Time #1--
nop ; 25.4 uS
nop ; 25.6 uS
nop ; 25.8 uS
nop ; 26 uS
HSync ; 26.2 uS -> 30 uS --HSYNC--
nop ;30.2 uS --Blank Time #2--
nop ;30.4 uS
nop ;30.6 uS
nop ;30.8 uS
decfsz tri9 ;31.0 uS
nop ;31.2 uS
nop ;31.4 uS
goto x9 ; 31.6
Code: Select all
movlw D'120' ;Blank Upper and Lower 120 Lines
movwf TopCount
movwf BotCount
Code: Select all
movlw D'6'
movwf LCount0
movwf LCount1
movwf LCount2
movwf LCount3
movwf LCount4
movwf LCount5
Code: Select all
HSync: macro
bcf PORTB, 3 ; horiz sync
nop
nop
nop
bsf PORTB, 3 ; horiz sync
endm
Code: Select all
HSync: macro; Begin Macro 0.0 uS
bcf PORTB, 3 ;0.2 uS horiz sync
nop ;0.4 uS
nop ;0.6 uS
nop ;0.8 uS
...
...
nop ;4.4 uS
nop ;4.6 uS
bsf PORTB, 3 ;4.8 uS horiz sync
endm ;End Macro 5.0 uS
Code: Select all
VSync: macro
bcf PORTB, 4 ; vert sync;1
nop;2
nop;3
nop;4
nop;5
nop;6
call Delay10mkS
call Delay10mkS
call Delay10mkS
call Delay10mkS
nop//47
;upto 36 works
bsf PORTB, 4 ; vert sync//48
endm
Users browsing this forum: No registered users and 5 guests