[Linux-parport] using ppdev instead of direct hardware access
stef
stef-listes at wanadoo.fr
Mon Jan 12 16:06:50 GMT 2004
Hello,
I'm in the process of adding ECP support for my parallel port
scanner, and I have trouble to see how to do it with ppdev. It uses such
sequences (addr are relative to parport address):
OUT +2, 4
OUT +1026,74 -> go to ECP FIFO mode
IN +1026=75 ->read ECR
OUT +0, A
IN +1026=75
IN +1026=75
OUT +1026,34 -> go to byte mode
OUT +2,20
OUT +1026,74 -> go to ECP FIFO mode
IN +1026=74
IN +1024= 0
IN +2=20
OUT +2, 4
OUT +1026,34 -> go to byte mode
I am far from understanding how to set to ECP FIFO or plain
ECP with the available ppdev ioctls. The ones I think I need are
marked obsoleted, and have no kernel code.
Also, I have still to figure from/to which addr read/write go.
Any hint is welcome.
Regards,
Stef
More information about the Linux-parport
mailing list