Path: utzoo!utgpu!water!watmath!clyde!rutgers!ames!amdcad!sun!pitstop!sundc!seismo!uunet!mcvax!hafro!krafla!geysir!eik
From: eik@os.is (Einar Kjartansson)
Newsgroups: comp.sys.hp
Subject: gpio bugs on HP 9000/840
Keywords: gpio 8bit lock afi 27114A
Message-ID: <107@geysir.os.is>
Date: 7 Feb 88 17:15:01 GMT
Organization: National Energy Authority of Iceland
Lines: 32

xxxx

Does anyone know of a way to get exclusive use of the 27114A
general purpose interface on HP 9000/840 .

I have tried several ways, such as 

afi = open("/dev/gpio0",O_CREAT,O_EXCL) ;

and

gpio_control.type = GPIO_LOCK ;
ioctl(afi,IO_CONTROL,&gpio_control) ;

According to my reading of the manuals either method should do the
job, but neither makes any difference.
I have also been unable to get the interface to function in 8 bit mode
( I can get it to report back that is configured as 8 bits, but it
always sends 16 bits out.) As the device on the other end (a Versatek plotter)
has an 8 bit interface this means that I must send double the amount of
data to the interface.

With this as well the numerous other software errors that we have run into,
talking to HP support has been a waste of time. The symptoms did not change 
when ve upgraded from HP-UX 1.04 to 1.20.

Einar Kjartansson 				eik@geysir.UUCP 
Orkustofnun 					eik@OS.IS
(National Energy Authority of Iceland)		mcvax!hafro!geysir!eik	
Grensasvegi 9					geysir!eik@hafro.uucp
IS-105 Reykjvik, Iceland
Telehpone:   354-1-83600  or  354-1-16407