I've updated the program to read as thus:
#include stdio.h
#include dev/ppbus/ppi.h
#include dev/ppbus/ppbconf.h
#include fcntl.h
int main()
{
int fd;
u_int8_tval;
fd = open(/dev/ppi0, O_RDWR);
val = 0xff;
while(1)
{
ioctl(fd, PPISDATA, val);
Shouldn't 0xff result in 5v outputs?
On Sun, 27 Oct 2002, Greg Shenaut wrote:
In message [EMAIL PROTECTED],
David Nicholas Kayal cleopede:
val = 0xff;
For this kind of testing, it is sometimes useful to use a value
like 0xaa or 0x55, and probe the adjacent lines--don't forget that
if
I don't have a printer, so I am not sure.
On Sun, 27 Oct 2002, Greg Shenaut wrote:
In message [EMAIL PROTECTED],
David Nicholas Kayal cleopede:
Shouldn't 0xff result in 5v outputs?
Sure, but in general you may get more information by using an
alternating bit pattern (aa/55), that's all.
In message: [EMAIL PROTECTED]
David Nicholas Kayal [EMAIL PROTECTED] writes:
: Shouldn't 0xff result in 5v outputs?
Depends on of the pins are negative logic, now doesn't it :-)
And most Parallel ports I've measured clock in at about 3.3V.
Warner
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:Depends on of the pins are negative logic, now doesn't it :-)
:
:And most Parallel ports I've measured clock in at about 3.3V.
:
:Warner
That sounds about right. I found a web page with the
circuit for a TTL output.
http://www.play-hookey.com/digital/electronics/ttl_gates.html
If
On Sun, Oct 27, 2002 at 04:31:46PM -0800, David Nicholas Kayal wrote:
#include stdio.h
#include dev/ppbus/ppi.h
#include dev/ppbus/ppbconf.h
#include fcntl.h
int main()
{
int fd;
u_int8_tval;
fd = open(/dev/ppi0, O_RDWR);
val = 0xff;
while(1)
{
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