mlh@houxw.UUCP (10/31/83)
I've got a problem with my CoCo and I'm wondering if anyone else has seen something similar, and maybe knows the reason and a fix. After I've been using my CoCo a while (64K, extended BASIC), I get what look like memory hits. One or two columns on the TV screen get three or four evenly spaced characters, all the same, typically a "$", where there was previously white space. Generally, the machine continues to operate, but once in a while it stops understanding commands. This problem only seems to occur when I have my JFD Disk Controller plugged in (by the way, I'm very pleased with their PLL circuit). Any help is much appreciated. Marc Harrison AT&T Bell Labs, Holmdel
sjt@sb6.UUCP (SIDNEY THOMPSON) (11/02/83)
The problem you reported seems to be common on the COCO. It does not seem to appear when using RS games but under any other situation seem to be common. Of the people I have talked to that use the COCO for FLEX or in the 64k mode it seems to be worse. I first saw this on a friends machine while we were trying to bring up OS-9. It is very frustrating to say the least. I would be interested to find if there is a cure since the friend says he has changed almost every chip except the SAM and the problem remains. Sidney Thompson
boehm@uw-june (Hans Boehm) (02/23/84)
I have a Coco (not Coco II) with a RS disk and controller. It seems to run anything using the RS disk format (e.g. Telewriter 64) without any problems. But when I try to format an OS9 disk it usually hangs somewhere in the process, and just keeps reading the same track continuously. I have also had problems with CRC errors on OS/9 disks written by the drive. Does anybody know what the OS/9 format utility does, and what might cause it to hang? Hans Boehm Boehm@uw-june (cornell,lbl-unix,...)!uw-beaver!uw-june!boehm
mstach@ihuxa.UUCP (Dan Hoelker) (03/29/84)
I have a similar, but less serious problem with one of my Coco disk drives. It seems to read and write all OS-9 and non OS-9 disks correctly, but bombs out when trying to format or backup an OS-9 disk. Fortunately the drive is new, so when it comes back from getting fixed I will tell what was wrong. I guess that it may be a stepping problem. Dan Hoelker ihuxa!mstach