Everyone (I hope) knows the weird partitions on the 1581. They weren't used too much because they're rather complicated to use, but I like them. Here's a little guide to these things.
1581 partitions must have these characteristics:
- a minimum of 120 Blocks (minus 40 blocks for the directory = 80 Blocks free)
- always start at sector 0
- the size must be divideable by 40
- they musn't allocate Track 40
Maybe these restrictions are the reasons because 1581 partitions weren't used often. But it's not too difficult. For creating a partition in the size you want it you have to do following calculations:
- the amount of blocks you need
- add 40 blocks for the directory
- raise the block number if its divisibly by 40.
To create a 1541 disk you have to calculate like this: 664+40 = 704. The next size divisibly by 40 is 720. That's all.
I'm using the standard Partition Aid tool from the 1581 Test/Demo disk. With key 4 you can select between different 1581 drives, key 3 shows the directoy and with key 1 you can swap between partitions. With key 1 you can create partitions.
First you enter the name of the partition. Then choose the track, either 1-39 or 41-80, so the directory track isn't allocated. Then follows the sector, it is always 0. If that's ok, the programm will ask if the partition should be created. You have to enter the name displayed in the partition directory and the ID, like formatting a disk. That's all. If you show the actual directory, you're already in the partition you just created.
These are some typical partition sizes:
1541 disk: 720 blocks (680 free)
near-1571: 1360 blocks (1320 free)
1571 full: 1400 Blocks (1360 free)
maximum size: 1560 blocks (1520 free)
Partitions are easy to handle, they could be renamed or deleted like files. Joker functions also work. Changing partitions is done with the / command, in JiffyDos @/tools selects a partition, @/ selects the root directory.
I like these things because you could organize things better. So I created a 1581 disk with four 720 block partitions to store the CMD Utility disks there. For emulators I created a game disk, using the HD-patched versions of Turrican and Katakis. I first I created an empty file MENU, then a divider file '-------------'. Now I created a partition about a 1571 size starting at track 5 for Turrican 1, a similar sized partition for Turrican 2 was starting at Track 41. Katakis is put in the root directory, I'll always wanted to add something in the directory that hides these files. Now I programmed a loader menu in BASIC with allow to select the games, after selection the program changes the partitions and loads the game. Of course this is easier as using 5 different 1541-images in an emulator. I hate changing disk images.
By the way, what's the best method to hide the following files in a director? I always know these "filename"+CHR$(0)+CHR$(0) tricks, but the directory is always a bit distorted after this method. What is a good solution for this?
