mstechca
New Member
This has literally beaten me for the past two days.
I hooked up the data pins of my hitachi controller compatible LCD to the data pins on the parallel port, and I hooked the parallel port's strobe pin to the clock pin on the LCD. I also connected a pull-up resistor to the strobe pin. The rest of the output parallel port pins are unused. The Busy, ack lines are set to ground, and the select printer pin is set high.
I have the following as my qbasic program to drive the port:
open "lpt1:" for output as #1
print #1,chr$(63)
print #1,chr$(15)
close #1
end
The first instruction seems to execute perfectly every time, but the subsequent instructions dont want to work.
I even tried to implement a one second delay between each print statement like this:
open "lpt1:" for output as #1
start=timer
do
loop until timer - start >= 1
print #1,chr$(63)
start=timer
do
loop until timer - start >= 1
print #1,chr$(15)
start=timer
do
loop until timer - start >= 1
close #1
end
and it still doesnt want to work.
this is why I wanted to do everything hardware based, where I can poll the busy flag on my LCD.
Can someone tell me what is going on?
I hooked up the data pins of my hitachi controller compatible LCD to the data pins on the parallel port, and I hooked the parallel port's strobe pin to the clock pin on the LCD. I also connected a pull-up resistor to the strobe pin. The rest of the output parallel port pins are unused. The Busy, ack lines are set to ground, and the select printer pin is set high.
I have the following as my qbasic program to drive the port:
open "lpt1:" for output as #1
print #1,chr$(63)
print #1,chr$(15)
close #1
end
The first instruction seems to execute perfectly every time, but the subsequent instructions dont want to work.
I even tried to implement a one second delay between each print statement like this:
open "lpt1:" for output as #1
start=timer
do
loop until timer - start >= 1
print #1,chr$(63)
start=timer
do
loop until timer - start >= 1
print #1,chr$(15)
start=timer
do
loop until timer - start >= 1
close #1
end
and it still doesnt want to work.
this is why I wanted to do everything hardware based, where I can poll the busy flag on my LCD.
Can someone tell me what is going on?