2.06 tos doesnt' fit

[utri007]

My mistake, I should have calculate pins. What are my options?

tos_2.06.jpg

[exxos]

You cannot install TOS206 onto a STFM.. The only method to do that is with the V2.X booster.

[utri007]

As you can see I have made some arrangements to get 2 chip TOS work. Would this work actually any 2 chip TOS? Current TOS is 6 chip Swedish 1.03? Do you have anything to offer me?

Booster would be nice, but I'm going to get Lightning IDE & usb board, not sure will it work with that?

tos_ram.jpg

[exxos]

If you have 6 chip TOS then max version you can have is TOS104.. (I never heard of 103).

https://www.exxosforum.co.uk/atari/store2/#0121

I have no idea if lightning is compatible with booster , I do not own one, but I assume not.

Maybe next year I will have TOS206 adapter board, I got the PCBs made a few months ago, but just no time to work on that project right now.

[utri007]

OK so I need to reverse those 1mb solderings. Do I need to remove 74LS11 from u68 or can I let it be?

[utri007]

Just bought 6 chips U.S.A TOS 1.04

PS It shouldn't require state or region, as there is no such a thing needed (or wanted) when posting to Finland.

[PaulJ]

If your getting the new LightningST it works great and provides a TOS2.06 decode signal. I would guess if you could get Exxos's ROM board that goes with the accelerator he spoke of and use the lightningST's 2.06 decode to feed Exxos's rom board.

[tzok]

All 1Mb EPROMs are too long, but that is not a problem, you'll easily find a wire wrap method to put them in. For 2 EPROMs you need just 47LS11, but to have TOS 2.06 (or 1.62) you need some additional address decoding logic (a GAL or a bunch of TTLs). If you want to reverse from 2 ROM to 6 ROM you just need to switch jumpers (solder pads), no need to remove the 74LS11.

[utri007]

no need to remove the 74LS11.

Thanks

If your getting the new LightningST it works great and provides a TOS2.06 decode signal. I would guess if you could get Exxos's ROM board that goes with the accelerator he spoke of and use the lightningST's 2.06 decode to feed Exxos's rom board.

Is this fact or "maybe"? I thought that 74LS11 does 2.06 decodong?

[PaulJ]

Thanks

If your getting the new LightningST it works great and provides a TOS2.06 decode signal. I would guess if you could get Exxos's ROM board that goes with the accelerator he spoke of and use the lightningST's 2.06 decode to feed Exxos's rom board.

Is this fact or "maybe"? I thought that 74LS11 does 2.06 decodong?

The 74ls11 converts the Chip Enables for 6 rom TOS to CE's for the 2 rom set. Has nothing to do with the decode which is for $FC0000 on pre TOS 2.06 versions.. 1.04, 1.02 etc. TOS 2.05 and 2.06 reside at $E00000 due to rom size which is larger (256K) instead of 192K. In the stand ST and MEGA ST this $E00000 decode signal does not exist. In order to use TOS 2.05 or 2.06 you need this decode signal which can be obtained by using an Exxos accelerator, lightning card, or a decode design of your own or building one of the many decode circuits out there. If you have decided to use the 6 rom 1.04 and disconnect the 1 meg short and reconnect the 256k shorting block the 74ls11 should be fine left in or removed. Its basically out of circuit. If it were me I would us the lightning card and "STFM KIT DUAL TOS & UBE BETA (NO ROM) £18 8 In Stock" in Exxos's store. You do need the correct motherboard to use this rom card so be sure you have the right motherboard. Lot of choices available to ya. :)

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