View Full Version : Why wont sysgen write the loader?

December 1st, 2017, 05:39 PM
I have a CompuPro 8/16 running Concurrent CP/M-86 3.1. I am using an HxC flashed Gotek FDD emulator for 8" drives. Emulated blank floppies successfully format to 1.2mb with 1024 sectors and the CCPM.SYS copies from a: to b: (pip b:=a:ccpm.sys) no problem.

When executing "a:sysgen ldrccpm8.86" it does not successfully write the loader to the formatted b: drive. The b: drive activity light flashes like something is happening but the loader does not get written and thus no CCPM.SYS is found when attempting to boot.

I have one software image that has a properly installed loader and does boot. I can make multiple copies of that image and copy a CCPM.SYS file over to it rendering a bootable disk. Id like to know how to make one instead of having to rely on a copy.

Or is this issue a weird bug in the floppy emulator?

December 1st, 2017, 07:16 PM
Does the first track remain MFM 1024/8? Or does the copy reformat to 128/26 FM? It was not unusual for 8" CP/M floppies to have a single-density boot track. Offhand, I don't recall if the Godbout boxes did that.

December 1st, 2017, 08:47 PM
When I look at the image which boots using the HxC floppy disk emulator software track analyzer it looks like there is an fm track.

December 1st, 2017, 08:56 PM
On the bootable image track 0 is FM with 128 sized sectors and track 1 is MFM with 1024 sectors

December 3rd, 2017, 09:38 AM
You cannot Sysgen the Compupro Loader from CDOS onto a single density 128 byte sector format floppy. Not enough room for the Loader. I haven't tried Sysgen with anything except 128 and 1024 byte sectors, and I know for a fact that while you can format IBM 3740 single-sided & single-density, on a Compupro, and you can read and write single-density, BUT you will not be able to sysgen or boot that single-density disk.

When running 8" floppies, IF you format 128 byte sectors, you are making UNBOOTABLE DISKS. For a Compupro, the Boot Tracks must be 1024 byte sectors Format the Disk 1024 BS.

To make Bootable disks, Format 1024 byte sectors. Tracks 0,1 must both be 1024 byte sectors. Then, you can Sysgen the Loader, and boot that disk (after transferring a CCPM.SYS file to the disk). If there is no CCPM.SYS file, the computer will ask you which SYS File to load (Compupro Distribution Disks have multiple CCPMXXXX.SYS files preassembled).

You cannot reassemble CDOS without DSDD 8" 1024 BS floppy or a hard drive because you can't get all of the necessary files (to reassemble the OS) onto a single 128 byte sector floppy. The earlier and smaller Compupro CPM-80 and CPM-86 OS could be reassembled on a single DSDD floppy if you strip off everything on a bootable disk, leaving only the Boot System, files to reassemble, and the Assembler, but the later OS (CDOS) cannot do that. They are just too big to fit on a 1.2mb floppy.