Linux-Hams archive - June 1998: SCC problems...

SCC problems...

Lars Petterson (ydn.vupwk@idm.fr)
Wed, 10 Jun 1998 13:55:53 +0200 (MET DST)


I've been looking into my problem with my SCC-cards a bit more.

The problem is garbled packets. These packets are not discarded but
sent to the applications which is bad...

I have seen this problem on our club stations two computers. Both
uses more than one card (one uses two DRSI-cards, the other two DRSI-
cards and one USCC>4-card). At my home station I am also using a DRSI-
card, but only one and do not see any garbled packets. (The DRSI-cards
are of type II, i.e. with two 1k2-modems.)

As far as I can tell the problem show up on stations using more
than one SCC-card (more than one SCC-chip) and only on port B.

So what could cause these problems? In the code one resets the highest
interrupt in use (IUS). According to another code for scc-cards I
have this should only be done for the A-port side. I.e.
OutReg(scc->ctrl,R0,RES_H_IUS);
should be changed into
OutReg(ctrl->chan_A,R0,RES_H_IUS);

Well, at least I thougth so... It sounded quite good... But the problem
is still there...

Is there anyone out there that have more than two SCC-cards in the
same machine and who can get the B-port to work on all SCC:s?

We use 486dx2-66MHz with 16 and 24 MB of RAM, 128 KB chache. Linux
2.0.33, ax25-utils-2.1.42a, scc-driver 2.4c.dl1bke

The system have worked on an 8088 with dos and bpq (two DRSI-cards) and
on an 386dx-25MHz runing dos, dv, bpq, nos, and fbb (two DRSI-cards)
whitout any problems whatsoever. I.e. it ougth to work in Linux also...

73 de Lars, sm6rpz

-- 
Lars E Pettersson        |  Chalmers University of Technology
doukh.zimmonuiy@swisscontrol.com  |  Gothenburg, SWEDEN