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130XE Reverse Option Key for Basic


Diskwiz

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Hello All,

 

I am about to burn an eprom for some OSs in my 130xe to make it easier for my son to use. I am planning on patching my stock OS with the hispeed patch but would also like to reverse the use of the option key so that Basic is disabled by default. Does anyone know how to modify the OS for this? I did search this forum and know there are some aftermarket OSs that have this built in, but not sure if any of them are available for download.

 

I am installing a 27c512 so I have some room for multiple OSs.

 

I am not looking for anything too fancy. I just would like high speed SIO and basic disabled and a second option of a 400/800 translator OS, in case.

 

Thank you,

Don

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Just taking a quick peek in the OS, it looks like OPTION is checked at $C49A. If $C49F is changed from BEQ to BNE ($F0 to $D0), that might do it as far as BASIC is concerned.

 

Thank you. I will try that and report back. I found out how to disable checksum, but how/where do I change the checksum value so that it is checked properly?

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OK... So I thought I would cheat by making the change at 0x49F on the rom and then run the patchrom from the hispeed patch archive thinking that it would generate the correct values. Nope. It never even changed the checksum value. After doing some searching, I found that byte 00 and 01 are the checksum values in the rom and that is how I found out what was going on. I subtracted 0x20 from the value (f0-d0) and resaved the file. I then ran patchrom and it generated a value 0x20 less than the stock HS patched rom, so I know it re-generated a checksum this time. Not sure what patchrom is doing, but maybe it does a checksum on the unpatched rom before creating a new one and if it fails, does not modify 00 and 01.

 

Anyway, I reburned an eprom (man these ti27c512's take forever to erase) and all seems to be working just like I wanted. Option is reversed and I have my high speed SIO for a device I created. I wish I would have done this 2 years ago when my son was more interested. He was 7 when I first created an SIO device on my Arduino and I was trying to make it easy for him to change drives.

 

Thanks Bryan, Rybags and Appendix 12 of Mapping the Atari. :)

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  • 1 year later...

There are single rotary switches, I suppose one might find one with a small screwdriver slot to select positions with, but you'd still have one switch on the case. Probably going to be pricey too. Oooh, just remembered a good one, it's on the back of some SCSI drive enclosures. It's a push button with three digitally encoded outputs and you just push for the next one. Used for drive number assignments, if this is drive six, push the button six times. Seems like it had a window with rolling number dial in it too so one would know right off what it was set for. I know this switch was on Syquest 200 meg removable cartridge SCSI drives as I use one for my Black Box. A bad enclosure might be had for shipping basically, but working units are getting rare at a decent price. Outrageous price, you can buy all you want. The switch was made and others similar, maybe even a four position one. Digi-key and mouser good bets.

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Holy cow...That was almost 2 years ago? I normally don't yank the 130xe out until December. Do you want me to see if it has the extended memory test? I don't remember. Been awhile, but it has the extra boxes or something...correct? I think I started with the stock OS, but I might have started with the later 130xe rom...

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No, don't bother yourself like that, but thanks anyway. I can put it in an emulator and test it myself which I haven't done just because I'm lazy and I don't have a real Atari up and running to use it with anyway. Yes, it should have four extra boxes at the bottom of the self test memory test. I can even do what you did here too with the OS I want, so really no biggy - I was just answering yes to 600XL question and didn't realize that the thread was 2012 until I woke you up, sorry about that. And thanks for offering your time like that, but when I can't get around to using an emulator myself it's just not the right thing to do bothering you at all. But now we do know - It could be either early or late 130XE OS.

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Woohoo, I just burned a 27c512 with Diskwiz's OS, XL-Fix OS, the original Rev.2 OS which was in 800XL's and a fourth OS I found somewhere. I didn't have time to make the switches and wiring for it so I simply bent up pins 1 and 27 and swapped the ROM for the EPROM and fired it up, Got test screen right away. ReBooted with the option key down -> BASIC. Hit shift-RESET and cold boot ! Love it, thanks !!

 

Next is replacing the Basic REv.B ROM with an EPROM. The 600XL has the extra solderings eyelets for an EPROM but gotta figure out if some jumpers have to be made/broken. Won't be running much Basic and if so it will be mostly Turbo Basic of course but .....it's just so much fun to hack this baby :):)

 

I'm surprised that all the XL's I've aquired recently still have Rev.B basic. I vividly remember that my 600 XL often crashed for no reason during typing in BASIC listings and I didn't know about the BASIC bug then. So I retuned the machine and it was gone for about three damn weeks !!! Worst weeks of my youth ;);) it came back with a nice explanation though and of course Rev, C installed.

Edited by Level42
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If I remember correctly, a 68764 or 68766 EPROM is drop in compatible with the BASIC mask ROM chip in the XL/XE models, as well as the BASIC cart. In the cart, you use one socket leaving the other one empty.

 

Those chips are a little expensive, and you must make sure your programmer supports the device.

 

I have had great success with them.

 

Hope this helps.

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Never heared about those EPROMS types. I got quite a few "regular" EPROM types here so I am tempted at extending the socket on the 600 XL. I can also confirm the high speed SIO routines work like a charm with my Happy 1050......should have done this OS mod a lot earlier, love it !

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Never heared about those EPROMS types. I got quite a few "regular" EPROM types here so I am tempted at extending the socket on the 600 XL. I can also confirm the high speed SIO routines work like a charm with my Happy 1050......should have done this OS mod a lot earlier, love it !

Some models of 600XL boards are configurable between mask ROM/2764 EPROM for BASIC, as per attached image. I don't know if other Atari models have this feature.

post-26063-0-70198100-1414642422_thumb.jpg

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Some models of 600XL boards are configurable between mask ROM/2764 EPROM for BASIC, as per attached image. I don't know if other Atari models have this feature.

attachicon.gif600XL-BASIC jumpers.jpg

That is exactly what I was looking for, thanks !!! although I didn't look closely at the board yet, but I did see there are four more positions next to the existing socket. I really want to go this way, already have the correct EPROM.

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That is exactly what I was looking for, thanks !!! although I didn't look closely at the board yet, but I did see there are four more positions next to the existing socket. I really want to go this way, already have the correct EPROM.

If your board has the 28-pin footprint for the BASIC socket then it likely has the indicated soldered in jumpers, I found out about this feature in the following post:

http://atariage.com/forums/topic/225608-wanted-600xl-basic-rom-probably-800xl-compatible-maybe-more/?do=findComment&comment=2994101

 

It was the 4 silkscreen marks by the jumpers that led me to investigate and confirm that they changed the socket configuration. A later post in the thread linked above mentions that some boards don't have the removable jumpers, and that traces must be cut.

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  • 3 years later...

This worked on my Atari 800 CORE for the MIST FPGA! I changed the name of the file to ATARIXL and renamed the .BIN to .ROM and I was able to run everything so far without changing to OSB. I was even finally able to get MULE to run on MIST. For some reason I could never get past the character selection screen before.

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  • 2 weeks later...

No problem! Here it is.

 

Oh also...it has the mod where if you hold the left shift button while hitting reset, it cold boots. Highspeed SIO patch V1.30 by Matthias Reichl.

 

Hmm, this is nice! only last patch that would be nice that comes to mind is the fast floating point routines.

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