cpm format error

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Alex - K3CIM

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Nov 2, 2021, 1:30:26 PM11/2/21
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ALL:  got a persisstant problem with formatting cpm H17 disks.

first, the drives work fine with hdos 2.0 and init H17 disks just fine.
they sysgen and boot just fine.

but when i try to format the H17 disks with cpm i get "Media error"
cpm formats h37 disks just fine.

not sure what is going on here....

any suggestions would be appreciated.

Alex B
K3Cim

Terry Gulczynski

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Nov 2, 2021, 1:54:01 PM11/2/21
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Are you certain the machine is running @ 2MHz while formatting under CP/M?
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Alex - K3CIM

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Nov 2, 2021, 2:03:45 PM11/2/21
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Terry, i am 99 % sure i am at 2 mhz. and as i stated it works just fine with hdos 2.0
going to try hdos 3.0 next

Alex - K3CIM

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Nov 2, 2021, 2:29:17 PM11/2/21
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hdos 3.0 comes back with "cannot format this disk"
and MMS format comes back saying "cannot format a 48 tpi disk in a 96 tpi drive"
 but the drives are 48 and listed in the mode command as H17 drives.
i am hoping that it is something obvious that i am not getting    :-))

Douglas Miller

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Nov 2, 2021, 3:41:33 PM11/2/21
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Just a wild thought, but is the step rate set too low (fast) for these drives? I'm not sure how to change that in Heath CP/M, nor can I tell what the default is for any of those OSes. MMS CP/M has a MODE.COM command that should allow you to examine/change the step rate.

I seem to recall that the "original" H17 drives couldn't operate at anything less than 30mS. It is also possible that the drive is in need of maintenance and not stepping according to spec.

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Alex - K3CIM

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Nov 2, 2021, 4:11:42 PM11/2/21
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Doug, all three drives go thru the test17 tests to completion without error.
all the way down to 8 ms per track on the seek test.

Douglas Miller

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Nov 2, 2021, 4:58:12 PM11/2/21
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The MMS format command should be checking whether your drive is 40 or 80 tracks. Do you hear it do 40+ steps in, then 40+ steps out? There may be other reasons for it to spit out that message, but it seems like MMS format may believe that the drive is 96tpi. Or else the MODEs are set wrong and it never tries to step the head.

Alex - K3CIM

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Nov 2, 2021, 5:44:06 PM11/2/21
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definitely 40 track drives.
tomorrow i will reseat the h17 board  a few times.

Norby

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Nov 2, 2021, 6:01:41 PM11/2/21
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I’m assuming that you are using the same diskette when doing init under HDOS and format under CPM and same disk drive. If it works with HDOS then make sure config.com the drive parameters are the same as in HDOS. It is possible format.com might be corrupted for the H17. Try using Heath original CPM diskettes and boot from H17.

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On Nov 2, 2021, at 5:44 PM, Alex - K3CIM <ka3...@gmail.com> wrote:



Steven Hirsch

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Nov 2, 2021, 8:14:34 PM11/2/21
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From memory, Heath CP/M determines the number of tracks by stepping inward by
80 tracks, then counting how many steps out are required before TRK0 is
asserted. This created a number of issues when using Gotek/HxC with my H89,
since it doesn't enforce a "stop" on inward step.

Les Bird

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Nov 2, 2021, 9:12:55 PM11/2/21
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I think for CPM there are a couple things that could go wrong.
Check that the disk rotation rate is correct.
Check that you’re getting sector pulses.
And most importantly check that the drive heads are clean.

CPM is way more sensitive to these issues than HDOS.

Les

Darrell Pelan

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Nov 2, 2021, 9:45:13 PM11/2/21
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CP/M from Heathkit comes with a CONFIGUR utility that tells CP/M how many tracks a disk drive has. The "can't format a 48 tpi " indicates CP/M thinks it is a 96 tpi drive. CONFIGUR also sets the step rate

  Darrell

Alex - K3CIM

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Nov 3, 2021, 9:29:36 AM11/3/21
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i have tried both 2.2.03 and 2.2.04 cpm format with the same results.
both drives are 40 track in configur.  i have them set for 20 ms set rate.

Norby

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Nov 3, 2021, 9:39:25 AM11/3/21
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Are you booting CPM from the H17 or H37?

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On Nov 3, 2021, at 9:29 AM, Alex - K3CIM <ka3...@gmail.com> wrote:


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Alex - K3CIM

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Nov 3, 2021, 3:29:31 PM11/3/21
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i can boot from the 37 ok, it wont boot but will read on the 17.
and i think this is the ahhh hah moment.
i belive my memory is fading in my old age of 68
i could swear that there was two disk cable connectors on the h89-17 board.
i just checked and found ONE. looked at two other non working 89s and they only had ONE.
i was under the impression that there was two and there were two "strings" coming off the board.
thinking this i thought the internal drive had a terminator pack for the one string and the two external 17 drives needed another terminator.
well today i opened up the 89 only to find that there is ONLY ONE plug for cabling the disk drives.
mine has a cable with a split, one to the internal and the other to the external drives.
i examined more closely and found that the internal drive does NOT have a terminator pack.
which is why at VCF when i took out the terminator at the end of the string all the 17s stopped working.
put the pack back and they worked again.
so in a few minutes i will see if the reseating of the 17 board worked or not.....
Alex

Alex - K3CIM

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Nov 3, 2021, 4:47:33 PM11/3/21
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after reseating the h17 board a few times....same results
went back to the hdos test17 program
internal drive seek test died at 26 ms
next did the option "D" drive checkout....no problems at alla
      did the "M" media option no bad sectors found
went back to the seek test and it ran all the way down to 8 ms no problems.
cpm still says "media error" trying to format
i was looking for the source for the format program and found that it seems to NOT be listed on the sebhc site.
was trying to see what in the program kicks out that error message.
will continue trying

Glenn Roberts

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Nov 3, 2021, 4:56:02 PM11/3/21
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Alex: I recall our discussion at VCF east about terminators.  The last drive (and only that drive) on the cable chain must have a terminator pack installed.  I think CP/M may be more sensitive to this than HDOS?  So the HDOS TEST17 may pass with flying colors but CP/M is more picky?

Alex - K3CIM

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Nov 3, 2021, 5:09:45 PM11/3/21
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correct Glenn, as we saw ...when i put the terminator back in the drives started working....with HDOS 2.0

Mark Garlanger

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Nov 4, 2021, 12:30:32 AM11/4/21
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The soft-sectored controller had 2 drive connectors, but the hard-sector controller only had 1.

I don't think we have the source for FORMAT, it wasn't released like all of HDOS was. I think someone will need to use a disassembler to get the source for that.

Are your drives the original WANGCO drives? They were only guaranteed to step at 30 mSec, although I've seen them go down to the teens, I've never seen them down at 8. If it's not the original WANGCO drive, what make/model is it?

Mark


Alex - K3CIM

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Nov 4, 2021, 2:10:27 PM11/4/21
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i believe the drives are old PC drives.  i am thinking now that i must have been remembering another vendors h17 board, maybe MMS???
this weekend i will hit the basement to find another 89 to swap out the h17 board and see if that makes a change
alex

Norby

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Nov 4, 2021, 4:19:24 PM11/4/21
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If this is on the H89 there is a 1K of memory reserved for the H17 to be able to boot. As this memory is not used by HDOS 2.0 , it will boot fine. As CPM and HDOS3.0 uses this region it will not boot if such RAM is not fully functional. I will check this RAM first to be operational.

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On Nov 4, 2021, at 2:10 PM, Alex - K3CIM <ka3...@gmail.com> wrote:



Mark Garlanger

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Nov 5, 2021, 12:10:11 AM11/5/21
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Isn't that reversed. CP/M and HDOS 3.0 will remap the main memory into the lower memory, but it's HDOS 2.0 which keeps the ROM and other lower memory, like the RAM for the H17 mapped. 

Norby

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Nov 5, 2021, 11:52:02 AM11/5/21
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That is true for the H8. When I build the H89-SBC I did what you described and it did not work for HDOS 3 and CPM. I had to reserved 1K of RAM just for the H17 as shown on the H89 schematics. After implementing such changes in HW the H89-SBC booted CPM and HDOS 3 fine.

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On Nov 4, 2021, at 4:19 PM, Norby <norberto...@koyado.com> wrote:

If this is on the H89 there is a 1K of memory reserved for the H17 to be able to boot. As this memory is not used by HDOS 2.0 , it will boot fine. As CPM and HDOS3.0 uses this region it will not boot if such RAM is not fully functional. I will check this RAM first to be operational.

Douglas Miller

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Nov 5, 2021, 12:07:36 PM11/5/21
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Note, once CP/M (and presumably HDOS 3) are booted, that 1K is not relevant, since the entire lower 8K is all RAM. The various ORG0 implementations may have operated slightly differently, but the H89 would "move" an 8K block from high memory to low memory, except in the case of 64K where the low 8K was simply not enabled until ORG0 is set. Depending on your point of view, "56K" is actually "64K with the low 8K disabled".

Alex - K3CIM

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Nov 5, 2021, 1:31:39 PM11/5/21
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i would think that would be mute since hdos 3.0 and cpm "can" boot from the H37 and run fine there.
its only when i try the h17s that it squaks.

Norby

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Nov 5, 2021, 2:05:43 PM11/5/21
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The H37 doesn’t use the reserved 1K of RAM that the H17 uses to boot? Can you boot from the H17 CPM from the H89 system?

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On Nov 5, 2021, at 1:31 PM, Alex - K3CIM <ka3...@gmail.com> wrote:



Douglas Miller

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Nov 5, 2021, 2:56:25 PM11/5/21
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The H17 "floppy" ROM only used that 1K for one special function (HDOS load device driver), that isn't involved in booting CP/M. I can't say what HDOS (2) does with it, but CP/M doesn't care once ORG0 is set. During actual boot of CP/M, I doubt anything depends on that RAM.

I'm not sure what problem we're trying to solve here... is it still the failures in FORMAT?

Joseph Travis

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Nov 5, 2021, 7:07:40 PM11/5/21
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It was mentioned previously, the drives are believed to be from an old PC. If that is the case, it is quite possible they may be 80 track,  dual speed drives.

When using this drive in a PC, with 40 track disks (8 or 9 sectors), the drive spins at 300 RPM and has to double step. When using 80 track disks, the drive spins at 360 RPM. In either case, these functions are software controlled.  The drives can be configured to spin at 300 RPM however they still need to be double stepped for 40 track disks.

This being said, I suggest trying a known good 40 track drive to determine and verify where the problem is.

Regards,
Joe Travis n6ypc




Douglas Miller

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Nov 5, 2021, 7:46:34 PM11/5/21
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This would be the most obvious explanation for the MMS FORMAT error message, as it refuses to format 40-tracks in an 80-track drive, because the 80-track drive record head produces too narrow of the signal to be reliably read in a 40-track drive (which has a wider head/track).

I guess the proof would be to try and format 80-track media in 80-track drive. With MMS CP/M, this is pretty easy to do, later versions of FORMAT even allowed you to change modes when you start FORMAT (otherwise MODE allows you to do that).

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