sbw@naucse.UUCP (Steve Wampler) (06/07/89)
I'm posting this to the net because I've already used Lenny and Gil far more than I paid them... I'm trying to get a 2nd hard drive running with ICUS' expansion card, and am having some trouble. Not being a hardware type, I'm hoping some one can point me in the right direction. New drive is a CDC Swift (94355-100) 100mb, 17ms 3.5" drive. 1072 cylinders, 9 tracks, 17 sectors/track, correct? The expansion board appears to be working, in that the revision level is recognized at P5.1, and using the CDC drive *in place* of the internal drive (I mean *in place*, same cables as original, powered from 3b1, etc.) works fine (which implies to me that the extra bit for tracks is working, and the WD2010 is running as well). However, every attempt to add the CDC drive as the second drive has failed. Using the expanded diagnostics disks, I can start the format process (expert command 2,2). The light on the drive lights up, so I'm reaching it. However, at the end of formatting, the process dies when trying to write the VHB, with the message "response 10". Other commands (such as 2,1) die with the same response. Here are some of the things I've tried: Shortening all cables to less than that suggested by ICUS: No change. Replacing all chips on the expansion board: No change. Removing the internal drive and leaving the CDC at the end of the 34 pin cable (nothing connected in the middle) and running the 20 pin cable directly to the motherboard instead of to the expansion board: No change, except the failure to write the VHB became a "response 4". This last one confuses me, just how is this different than the case that worked above? Just the cables, so nearly as I can tell. Correct? Given the above, my plan is to rebuild all the cables and see if that fixes it. However, I'm 150 miles from the nearest store that carries the connectors, so that's going to take a day or so to try out. In the meantime I'd like to check out all other possibilities, to ensure that it's not something else. Er,... what are the other possibilities? Keep in mind I don't understand hardware. I doubt it makes any difference, but I put a COMBO board in slot 3. Would it make any difference if it were in some other slot? Thanks for any help!!!
jbm@uncle.UUCP (John B. Milton) (06/08/89)
In article <1479@naucse.UUCP> sbw@naucse.UUCP (Steve Wampler) writes:
[ problems with (Lenny & Gil)'s second HD board. ]
Sounds somewhat similar to the problems I am encountering with my board. I
should soon have it set up on a logic analyzer, so I may soon have some
suggestions. For right now:
1. Reinforce ground & +5
2. Shield it (what the heck)
3. Try some 2k pullups at the UNIXpc end of things on the high speed stuff.
4. Try a large cap across +5 & ground on the daughter board.
5. re-orient the long wires going across the bottom of the mother board.
6. Swap the drives (1<-->2)
7. Please post your findings
Error status register in the WD1010 (excerpt from HwNote13):
Bit 7 Bad Block Detect. From what I can tell about how things are done on
our systems, this feature is not used. We use a direct mapping method where
the position of bad blocks is determined by the bad block table. If this
gets turned on, it is some kind of glitch on the disk.
Bit 6 CRC Data Field. This one deserves a direct quote:
"This bit is set when a CRC error occures in the data
field. With Retry enabled, ten more attempts are made
to read the sector correctly. If none of these attempts
are successful, the Error Status is set also (bit 0 in
the Status Register). If one of the attempts is suc-
cessful, this bit remains set to inform the Host that
a marginal condition exists. However, the Error Status
bit is not set. Even if errors exist, the data can be read."
On our machiones, if bits 7, 5, 1 or 0 are set or if the error register is
not zero!, or if there was DMA trouble, an HDERR message will be printed.
This is extremely good. It means every time there is the slightest flicker
in the data, you will get an error message. If you get only one, the error
is probably transient and does not mean anything. You should NOT try to
lock out the block! If you get a bunch of CRC errors, but a good read,
this is probably a weak spot and should be locked out.
Bit 5 Reserved. Always zero.
Bit 4 ID not found. Like CRC, this bit is set when the ID field for the
requested sector can not be found, or has a bad CRC.
Bit 3 Reserved. Always zero.
Bit 2 Aborted Command. Should never happen on our system. If you get it, it
probably means BAD power line trouble.
Bit 1 Track Zero Error. This is very bad, and usually indicates a very bad
hardware failure in the drive, so you'll never see it until you get a
second hard drive on your system :)
Bit 0 Data Address Mark Not Found. Yet another thing not found.
Status 10 is bit 4 on, ID not found. This means it couldn't find the sector,
let alone what data is in the sector. The status 04 is confusing. This is
bit 2 on, aborted command. My remark above probably does not apply. It can
mean that the UNIXpc timed out waiting for something from the drive, and the
driver cancelded the request. Perhaps it was waiting for drive ready, or it
was waiting for ANY data to come in and syncronize the chip. Hmm.
John
--
John Bly Milton IV, jbm@uncle.UUCP, n8emr!uncle!jbm@osu-cis.cis.ohio-state.edu
(614) h:294-4823, w:466-9324; N8KSN, AMPR: 44.70.0.52; Don't FLAME, inform!