How long to create a new blank hard drive image?

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Terry Fox

Jul 29, 2021, 1:38:48 PMJul 29
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Hello all,
Recently I purchased one of these emulators to be used with a newly acquired Kaypro 10.  I was able to successfully read the original MSI HH-612 (306 cylinders, 4 heads) 10MB hard drive, and emulate it.

I wanted to archive that image and build a new, blank 10MB hard drive, so I followed the instructions “If you didn’t read a disk to emulate…”  verbatim using those same parameters (—cylinders 306 —heads 4).  The first time I ran mfm_emu, it took about 12 hours, and eventually came back to the Unix prompt.  But, it didn’t work right after rebooting.

The second time I ran mfm_emu, it started up and ran for over 30 hours before I killed it.  In both circumstances, after I started it, I saw a series of lines like this:
select 1 head x
Where head x is 0-3

That seems right, but should it take over 30 hours to setup a 10MB drive image?  Note taht I have not gotten to the Kaypro low-level formatting yet.
Thank you all!

Joan Touzet

Jul 29, 2021, 1:59:10 PMJul 29
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This could be due to the performance of the storage. If you're using the on-board flash on the BeagleBone, it can be very slow, especially for writing. (Reads are much less of a problem.)

Try adding a USB flash drive to store the data, and run the command on that drive instead. You can also try a microSD card.

David Gesswein

Jul 29, 2021, 8:29:05 PMJul 29
It takes less than 30 seconds. After it creates the file it starts running
as an emulator so it shouldn't exit. The print of the head changing is
the head select lines to the emulator changing.

If you are just wanting to create the file you can ^c after you see lines

1:test 2 0
1:test 3 0
1:test 4 0
select 0 head 0
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Terry Fox

Jul 29, 2021, 11:49:41 PMJul 29
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Thank you David!
I was confused about it doing all the select messages.  In addition, I forgot that the Kaypro wants to format drive 2&3 instead of 0&1.  It's now moving along formatting.

Did you ever have one of those days where EVERYTHING electric/electronic stopped working right?  That was here today.  From my watch to streaming TV to the new thermostat all failing/acting up, not to mention the computers hosing up...
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