Reconfiguring the hard drives

As shipped, the MISE's hard and floppy drives are organized as described here. Some users may wish to reconfigure this arrangement, to have more or fewer hard drives, hard drives of different sizes, or a different number of floppy drives.

Before attempting any of these steps, make a backup of your CF card, or use a CF card reader/writer to dump an image to your PC. That way if something goes wrong you can recover your system.

When creating a hard drive, its size will be: cylinders * heads * 8KB.

Removing and creating hard drives

In order to re-arrange your hard drives you will first need to remove one or more from the system. If you wish to remove all hard drives and start from scratch, skip this section.

Let's assume you want to remove drive :5. Start by disabling the drive:


Disabling the drive does not remove its assignment in LDOS. If you ENABLE the drive at this point, nothing will have been changed. To permanently remove the drive (not necessary if it's a floppy drive):


This will free the drive's disk space allocation for new drives to be created. The drive, if re-enabled, will become the lowest-numbered unused floppy.

Proceed to remove drives :4, :3, etc. in the same manner until you reach the desired arrangement. It's recommended that you remove the highest-numbered drive first and proceed downward, to leave the maximum amount of contiguous free space on the disk without any "holes". Do not remove drive :0, which would render the hard disk system unusable. Skip to the next section if you really want to start from scratch.

Next, if desired, create new hard drives to replace the ones you've removed, starting with the lowest-numbered:


This will generate several prompts. The "drive address <1-2>" is 1 for the Primary and 2 for the Secondary IDE device. "F/R" means fixed vs. removable. Use Fixed.

The partition's number of heads controls the number of heads assigned to the logical drive. It's recommended that you always use the maximum of 8 heads.

The number of cylinders controls how many will be assigned to the drive. The default value shows the maximum number that can be used. It is strongly advised that you use 203 or fewer cylinders because LDOS doubles the size of its file allocation units for any larger number. In addition to wasting disk space, this can cause problems with software including LDOS itself.

If the geometry of the new drive doesn't match the drive that previously occupied its disk space, or if the previous drive was corrupted, you will be advised that the new drive appears to be unformatted. Important: If you receive this message, you must immediately format the new drive, because certain LDOS commands will corrupt its Drive Code Table (DCT) entry.

If you don't see the message, it means that your new drive appears to match the physical geometry of an old drive. If this is not what you intended, it's advisable to re-format the drive.

See here for information on formatting hard drives.

Continue creating hard drives until you run out of drive numbers or reach the maximum of 1024 cylinders per physical IDE disk. Finish by executing SYSTEM (SYSGEN) to save your changes to disk.

Starting from scratch

If for some reason you really want to remove and reconfigure all the hard drives, read on. This is not something most MISE users will ever need to do. There are two main approaches.

One way: Re-initializing the primary CF card from floppy diskettes

  1. Create MISE system floppies.
  2. Insert and boot the MISE3 floppy by holding down <SHIFT> during reset. The following instructions assume that your first hard drive will be created as :4, allowing up to 4 floppy drives, :0 through :3, to be accessed during this procedure. Only one floppy drive is assumed, though.
  3. Create the boot partition. Enter SYSTEM (DRIVE=4,DRIVER="IDEROM/CMD"). Answer the prompts as described in the previous section. Immediately format the drive after creating it.
  4. Remove the MISE3 floppy and insert the MISE1 floppy. Then BACKUP :0 :4 (S,I).
  5. SYSTEM (DRIVE=4,SWAP=0) to make the hard disk partition drive :0.
  6. Remove the MISE1 floppy and insert the MISE2 floppy. Then BACKUP :4 :0 (I).
  7. Remove the MISE2 floppy and insert the MISE3 floppy. Then BACKUP :4 :0 (S,I).
  9. Remove the MISE3 floppy and insert the MISE4 floppy. Then BACKUP :4 :0 (I).
  10. Create additional partitions as described in the previous section. Use the DEVICE command to determine drive assignments, and use SYSTEM (DRIVE=...,SWAP=...) to move hard and floppy drives where you want them.
  11. SYSTEM (SYSGEN) to save your changes to disk.
  12. Reboot to test the new configuration.

The basic system created by this procedure does not contain all the files that came with MISE. You can download additional files from this website, and copy them to MISE using FTP. Once you have all the files, run DO ACCESS to set the correct passwords and permissions on all the files. This script will also help you detect files that are missing.

Another way: Initializing a second CF card

This assumes you have the default logical drive number setup (hard drives :0 through :5, floppies :6 and :7).

  1. Power down the TRS-80 and MISE.
  2. Insert a second CF card into the Secondary IDE slot on the back of the IDE/CF adapter, after reading the warning here.
  3. Powerup and boot from your Primary IDE disk.
  4. Select a drive to disable, to temporarily free a drive number for your new partition. Choose either a hard drive or an unused drive number. Using hard drive :5, SYSTEM (DRIVE=5,DISABLE,DRIVER="IDEROM/CMD").
  5. Answer the various prompts, entering "2" for the drive address. This selects the Secondary IDE device. The new drive doesn't have to be the same size as the existing one, but it should be large enough to hold the entire current contents of drive :0.
  6. IDEFORM :5.
  7. BACKUP :0 :5 (S,I). This backs up your LDOS system onto the new drive.
  8. SYSTEM (DRIVE=5,SWAP=0). This makes your new drive :0.
  9. At this point you can create more drives, or copy files to your new drive(s). However it is IMPORTANT that before you continue, you DISABLE and then IDECLEAR any remaining drives on the Primary CF card. If you do not, additional drives you create after moving the Secondary CF card to the Primary slot (see below) may have incorrect starting cylinder numbers. The following command will disable and clear all logical hard drives that are not on the same physical drive as :0:
  10. SYSTEM (SYSGEN). Note that these last two steps do not affect the configuration of the CF card in the Primary slot since drive :0 is now assigned to a logical drive on the Secondary card, and the new CONFIG/SYS file is written to drive :0.
  11. Power down the TRS-80 and MISE. Remove the Primary IDE CF card. Move the Secondary IDE CF card into the Primary slot.
  12. Power up and boot MISE. The ROM driver automatically detects that the boot drive was created in the secondary position, switches its DCT entry to the primary position, and disables drives that were in the primary position.
  13. Create additional partitions as described in the previous section. Use the DEVICE command to determine drive assignments, and use SYSTEM (DRIVE=...,SWAP=...) to move hard and floppy drives where you want them.
  14. SYSTEM (SYSGEN) to save your changes to disk.
  15. Reboot to test the new configuration.

Or to simplify matters, just make a mirror-image backup to the second card:


The secondary CF card need not even be formatted. See the backup utility page for more details.

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