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  1. As far as I can remember there is only 2 BIOS version. One for M models and one for K models. I seem to remember that one of these versions can work on the K and M models, while the other version can only work on one model. It seems to me that the subject had already been approached, maybe in another forum, maybe by myself... And the difference between the 2 BIOS was the initialization startup, of the video I believe.
  2. ... well just 2 things: The Jaguar Chipset was originally designed to operate at 40MHz. Its performance was revised downward when it was modified to work on the Jaguar console. Lower frequency, 16bits 68000 CPU interface instead of 32bits 68030 (and therefore 16bits also for the DSP since it shares the same interface), 24-bit address BUS instead of 32, less Bank memory and less Bank type (originally 128MB total address space: 2 Bank of ROMs 16MB each, 1 Bank of SRAM 32MB, and 2 BANK of DRAM 32MB each), no more Falcon mode, etc. I do not know if we can get better mapping performance using ROM instead of DRAM (ROM to DRAM instead of DRAM to DRAM). In the Jaguar the external data bus is common to the whole system and there is no funnel as in the TT. So the data must first pass necessarily by TOM to be eventually shifted and replaced again on the BUS. On the other hand, I do not know if TOM is able to prepare the access to the DRAM (CAS/RAS lines) at the same time that it makes the accesses to the ROM and does the shift, and vice versa. In fact, I do not know if TOM is able to access the external 24bits address BUS at the same time as it accesses the CAS/RAS lines of DRAM (ROM to DRAM or DRAM to ROM). Internally yes (GPU local RAM to DRAM for example).
  3. If you talking about retro-modding, the messageS are still there.
  4. wtf is going on here ? is this a weather channel ?
  5. there are some shops that sell Jaguar clothing
  6. 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.
  7. Here -> 82F25E: 0079 0018 00F0 0000 OR.W #$18, MEMCON1 Bit 3&4 of MEMCOM1, value 3 = 5 cycles And this is right after the Joystick test subroutine at the beginning.
  8. I quickly looked at the ROM a while ago, and it seems to me that they were changing the ROM speed access.
  9. 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.
  10. Hello, Does anyone know the differences between TOM version 1.0 and 1.1?
  11. How do we know where we are in the queue ? Is there a counter or something like that ?
  12. Did anyone test the 5-clock clock timing for ROM access with the SD Card? I think if someone manages to run Battlesphere Gold, then it certainly means that the SD card accepts 5 cycles because Battlesphere Gold changes the access speed to 5 from the very beginning.
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