TOM revision 1.0 & 1.1 differences

[DEATH]

Hello,

Does anyone know the differences between TOM version 1.0 and 1.1?

[kskunk]

I don't think there's any difference you'd notice. I looked into this a long time ago, and found:

 

1) Tom V1.0 made by Toshiba in December 1993.

2) Tom V1.1 made by Toshiba in March 1994.

3) Tom V1.0 made by Motorola in September 1994.

 

The dev manuals don't mention any difference, but we can also check the netlist (design) for Tom. The netlist does not show any changes in the time period between V1.0 and V1.1, so I think the design itself is unchanged. Instead, it's probably a change in the chip process or implementation - something to reduce cost by yielding more good chips.

 

The netlist does show changes between Motorola and Toshiba chips. In fact, they are quite different implementations of the same design. Still, despite major differences between Toshiba V1.0 and Motorola V1.0, I haven't heard of people noticing problems.

 

These kinds of changes are typical. They save a buck or two, and multiplied by 100K units, that's worth the effort. But unless you screw it up, developers and customers shouldn't notice a thing.

[Clint Thompson]

1 hour ago, kskunk said:

I don't think there's any difference you'd notice. I looked into this a long time ago, and found:

 

1) Tom V1.0 made by Toshiba in December 1993.

2) Tom V1.1 made by Toshiba in March 1994.

3) Tom V1.0 made by Motorola in September 1994.

 

The dev manuals don't mention any difference, but we can also check the netlist (design) for Tom. The netlist does not show any changes in the time period between V1.0 and V1.1, so I think the design itself is unchanged. Instead, it's probably a change in the chip process or implementation - something to reduce cost by yielding more good chips.

 

The netlist does show changes between Motorola and Toshiba chips. In fact, they are quite different implementations of the same design. Still, despite major differences between Toshiba V1.0 and Motorola V1.0, I haven't heard of people noticing problems.

 

These kinds of changes are typical. They save a buck or two, and multiplied by 100K units, that's worth the effort. But unless you screw it up, developers and customers shouldn't notice a thing.

I believe the Toshiba chips (K series) are not compatible with the second revision of the Jaguar main boards, so they have to go on the original 1993 PCB run. The same goes for the Motorola chips, and will only work with the 2nd 1994 PCB revision M series boards. I haven't tested this first hand but I do believe the word of Bradley in regards to these chips and compatibility issues between the revisions (of manufacturers Toshiba vs Motorola and not so much of the version number itself).

 

You will notice that the resister jumps on the M series are not present, so they must have fixed something in that regard to the chips during their Verilog update when switching to Motorola and possibly a minor change to the PCB itself and by doing so, resulted in the older chips into being incompatible.

[+CyranoJ]

There are certainly some differences as years back when working on Beebris and SFDX we found that it would only work on one of them.

 

It was to do with the way interrupt latches were cleared [EDIT: on the GPU Object Interrupt], iirc.

[DEATH]

Your answers lead me to many other questions

1/How to know which is the manufacturer of the chip? In my jaguar I have TOM v1.1 without the manufacturer's logo and JERRY 1.0 with the Motorola logo. Knowing that there was no v1.1 by Motorola, I conclude that it is a Toshiba. But then why Jerry is Motorola? There was no version of Jerry by Motorola?

2/...and in relation to the previous question, Saint said (somewhere in another topic related to SD Card) he had compatibility issues between Jerry version 1.0 and 1.1 ... So there are different versions of Jerry? And if so why I have a mix in my Jaguar. It's confusing.

3/You say that looking at Netlist we do not see differences, but I have only one version of Netlist (found on Torlus GitHub by the way), there are several?

4/Also in another topic, SPCD or ZEROSQUARE said there was a compatibility issue between the existing 2 BIOS and the motherboard versions and/or TOM and JERRY versions. More precisely one BIOS can work with all versions of motherboards/chips but the other can only work with one version. Are you aware of this ?
On this point I am not totally surprised. I disassembled and quickly looked at the BIOS (I do not know which version) and from the "very" beginning (actually in the bootcode and at the beginning of the "init" code AKA "Andy"), the code is "full" of bug, duplicate routines, bad optimization … so,  if there is a difference, even minor between the versions of TOM and JERRY, it would not be surprising if there was a problem of software compatibility, especially if this incompatibility is linked to registers initialized by the BIOS and that we are not supposed to change afterwards.

[kskunk]

7 hours ago, CyranoJ said:

There are certainly some differences as years back when working on Beebris and SFDX we found that it would only work on one of them. It was to do with the way interrupt latches were cleared [EDIT: on the GPU Object Interrupt], iirc.

That makes sense! I can see changes in the Object Processor for the Motorola version: There's a "Motorola TOM" comment in OBDATA.NET with the previous logic commented out. In the same file, there are other references to TOM1/TOM2, so the OP is probably an area that saw changes after V1.0.

 

Do you remember any more details? Were there any mentions in the dev docs?

[kskunk]

33 minutes ago, DEATH said:

1/How to know which is the manufacturer of the chip? In my jaguar I have TOM v1.1 without the manufacturer's logo and JERRY 1.0 with the Motorola logo. Knowing that there was no v1.1 by Motorola, I conclude that it is a Toshiba. But then why Jerry is Motorola? There was no version of Jerry by Motorola?

If it says "JAPAN", that's Toshiba. The number starting with 6SC is a Toshiba ASIC process number, telling you the die size, density, layer count, etc.

Quote

2/...and in relation to the previous question, Saint said (somewhere in another topic related to SD Card) he had compatibility issues between Jerry version 1.0 and 1.1 ... So there are different versions of Jerry? And if so why I have a mix in my Jaguar. It's confusing.

 

4/Also in another topic, SPCD or ZEROSQUARE said there was a compatibility issue between the existing 2 BIOS and the motherboard versions and/or TOM and JERRY versions. More precisely one BIOS can work with all versions of motherboards/chips but the other can only work with one version.

I don't have any first-hand knowledge of these issues, but CryanoJ has at least one explanation above, about differences in the Object Processor.

 

Normally, in mass production, you try to use every component in stock, even if it means mixing and matching chip revisions and PCBs. So, where possible, like on your board, they did! The fact that your Jaguar works fine means the differences must be very minor.

Quote

3/You say that looking at Netlist we do not see differences, but I have only one version of Netlist (found on Torlus GitHub by the way), there are several?

No, there's only one. But, there's a lot of history in the netlist! For example, you can see that we have the Motorola version, and it came later. You can find parts of the Toshiba version commented out. You can see dates here and there, marking when bugs were fixed. Also, you can see bug numbers, which give some sense of when they were found and fixed. (Higher are probably later.)

[Zerosquare]

4 hours ago, kskunk said:

Were there any mentions in the dev docs?

As far as I know, there is absolutely no mention of the different versions in the dev docs.

 

4 hours ago, kskunk said:

The fact that your Jaguar works fine means the differences must be very minor. 

I did some limited testing a while ago. If I remember correctly, one of the two ROM versions seemed to work regardless of the hardware version ; the other one didn't work reliably on one of the two hardware versions (it didn't boot every time).

 

I didn't look into it in depth, but one of the differences between the ROM versions are the values used to initialize the video registers: some of them are different.

 

5 hours ago, DEATH said:

the code is "full" of bug, duplicate routines, bad optimization …

It's an Atari console. What did you expect?

[DEATH]

28 minutes ago, Zerosquare said:

 

I didn't look into it in depth, but one of the differences between the ROM versions are the values used to initialize the video registers: some of them are different.

 

I just (right now ) look at the 2 version of the BIOS (K&M) that i found earlier, and there is a "major" difference at the VERY beginning  (3rd instructions !). The "m" version executes a delay loop (simple "dbnf d0" with a start value of -1). This could be very important to let the chips warm up in the "m" version of Jaguar, and of course has no effect on the "k" version who don't need it. But, if you use the "k" BIOS (who does not have the delay loop) with the "m" version of Jaguar (need delay), this could end up with bug or crash… This is just speculations.

[+CyranoJ]

7 hours ago, kskunk said:

That makes sense! I can see changes in the Object Processor for the Motorola version: There's a "Motorola TOM" comment in OBDATA.NET with the previous logic commented out. In the same file, there are other references to TOM1/TOM2, so the OP is probably an area that saw changes after V1.0.

 

Do you remember any more details? Were there any mentions in the dev docs?

 

Nothing in the docs (Shock!) - All I can remember is it was to do with shutting the interrupt down on one revision it would hang. I probably wrote something snarky in the source, I'll check it out when I have time

 

Nope, nothing in the source regarding what was going on.  I have memories of attempting the make the interrupt stop, but the code that's left behind loops on the GPU waiting for a flag, then just mashes 0 into G_FLAGS and G_CTRL lol.

Edited September 15, 2019 by CyranoJ
[Updated]

[Clint Thompson]

After digging through archives this evening, I may have been incorrect in my statement above about a 2nd revision board having been released and now it seems I can't confirm that any 1994 Jaguar PCB boards were ever actually produced. All Google images return 1993 boards and even my own Model M board is 1993.

 

Without everyone ripping apart their Model M Jaguars, can anyone confirm if they have or have seen a Jaguar PCB dated 1994 or is every Jaguar indeed 1993 only?

 

Edited November 26, 2020 by Clint Thompson