Odd Apple II+ Mod/Behavior

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Odd Apple II+ Mod/Behavior

Hi folks!

 

I have a friend who has an Apple II+ with a slight modification that allows them to boot from either the first or second slot.  (Slot 0 or slot 1)

 

Their goal is to be able to have a 16K language card in Slot 0 and a ROM card in Slot 1 - and be able to boot off of either.

 

While this appears to be working, they do not get an autoboot to Basic unless they have a floppy loaded.

 

I would have thought it would autoboot to the Basic prompt, but that isn't happening.

 

Was this a common modification?  And would anyone have any idea why it doesn't autoboot to Basic?

 

I don't have ready access to this computer, so if we need photos I'll have to reach out to the owner and ask them to send me some.

 

Many thanks!

 

Jenifer

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This is not a common mod.  In

This is not a common mod.  In fact it doesn't quite make sense.  Why would they want to boot from a RAM card?  At power-on the card will not contain a bootable image.

 

The behavior of not getting a BASIC prompt unless you have a bootable floppy is completely normal.  If you don't want to boot from floppy you hit RESET (or ctrl-RESET if your keyboard is set up that way).

 

Normally what you want is to boot from a floppy drive in slot 6.  Or something else like a hard drive in slot 7, or some kind of flash media device like a CFFA.  If you have a floppy controller installed and no floppy in the drive it will seek forever (which is what they're seeing).  If you have a floppy it will boot from it, assuming it is a bootable floppy.

 

If you do not have a floppy controller installed it will either drop you off in Applesoft if that is available from ROM (either mother board or ROM card with the switch installed to that) or if you have Intbasic selected, you should get a monitor prompt (*).

 

What exavtly are they trying to do anyway?

 

A BASIC prompt without any DOS loaded is not very useful unless they plan to use tape for storage, and that seems highly unlikely.

 

 

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This configuration is a bit

This configuration is a bit problematic, as there is nothing in hardware that would prevent both the Language card in slot 0 and the ROM card in slot 1 from both being active at the same time.  The  behavior  of the Language card defaults to enabled, so the firmware card in slot 1, should have it's switch set to disabled.  Normally, switching to the ROM card would require running some little program running out of DRAM that would turn off the language card and enable the firmward card in slot 1.  

 

The DMA OUT signal in one slot is connected to DMA IN signal  in the next highet slot and is used by firmware cards to disable cards in lower numbered slots that are ajacent to them.   This feature was not implemented by language cards.  I believe that there might be a mod for the language card that would watch for DMA IN being assertted and disable itself if true.  If this mod is added, it should be bootable on either card by setting the firmware card switch appropriately.  

 

Autostart ROMs will attempt to boot to BASIC off of floppy, but be aware that the language card also needs to load BASIC off floppy into it's memory before you can get the BASIC prompt.  Not all Apple floppys will have a image of BASIC installed on them. 

 

Regards,

Mike Willegal

 

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1978AppleII wrote:Hi folks! I

1978AppleII wrote:

Hi folks!

 

I have a friend who has an Apple II+ with a slight modification that allows them to boot from either the first or second slot.  (Slot 0 or slot 1)

 

Their goal is to be able to have a 16K language card in Slot 0 and a ROM card in Slot 1 - and be able to boot off of either.

I have an integer Apple II with this same configurtion. Applesoft is on the ROM card and I've got a multi-bank, 64K language card. DOS 3.3 needed a patch to support this configuration. There's an article on how to do it in Call-A.P.P.L.E. I forget which issue; it's probably in 1982-1983.

 

As others have said, this is a non-standard configuration, but it was not unheard of back in the day, and there are patches and ways to do it.

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I've used a 16k RAM card in

I've used a 16k RAM card in slot 0 with an Apple ROM card in another slot in a ]'[+.  That doesn't require software mods.  The only mod I had to make was to put the toggle switch on the back of the ROM card on a cord so I could put the card in other slots.  Normally it will only fit in 0, 2 or 4 because of the way the notches in the back of a ][+ case were.  However, to switch between INTBASIC and Applesoft I had to flip the switch and then hit reset or power cycle.  There may be a patch to DOS 3.3 to allow the ROM change through software, but I never had a need for it.  Most of the time the manual switch was enough.  Most of the time what I was actually doing was using the ROM card to crack copy protection by allowing a forced entry to the monitor on reset.  I also put a 6116 2kx8 SRAM in the empty socket of the ROM card that gave me some space to relocate some RAM that would normally be destroyed during reboot.  I also had a modified F8 ROM in there at one point (I think the one by The Freeze), although the card currently has the original Apple non-autostart F8 in there so I later reversed that at some point.  Probably after I got a Wildcard and didn't need the ROM card for cracking as much.

 

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I made one mistake in my

I made one mistake in my previous message.  With the language card, if it can't find the correct version of basic on the motherboard, it will download it from floppy.  I think if it can't be found in either place, a message something like language not available will be displayed.

 

regards,

Mike W

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softwarejanitor wrote:I've

softwarejanitor wrote:

I've used a 16k RAM card in slot 0 with an Apple ROM card in another slot in a ]'[+.  That doesn't require software mods.  [...]  However, to switch between INTBASIC and Applesoft I had to flip the switch and then hit reset or power cycle.  There may be a patch to DOS 3.3 to allow the ROM change through software, but I never had a need for it. 

That's exactly what I was referring to in my post. A patch to DOS 3.3 to support both Language Card and ROM card. I know this exists, because I read about it in Call-APPLE.

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Yes, but it is only necessary

Yes, but it is only necessary if you want the switch to happen automatically when you run the opposite kind of BASIC program from what you currently have enabled in ROM.  I think there are also DOS 3.3 commands to switch between INT and FP, and that with the patch they will work with the ROM card in another slot and you can still use the RAM card for other things.  Normally with just the RAM or ROM card in slot 0, that just works, but Apple never expected people to put both a RAM and ROM card in the same machine.  If you don't care about the software switching and are willing to just flip the switch on the ROM card and hit RESET, then you don't need to bother.

 

 

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