Hi. Correct me if I am wrong, but isn't the 1541u a cartridge meant to be connected to the expansion port of a real c64 to emulate 100% a 1541 drive ?
If you connect the 1541u to the expansion port only, it won't work correctly. The 1541u is an amalgam of a multi-purpose expansion card (including cartridge emulation, DMA data transfers, etc.), and a drive emulator (via IEC). You have to connect it to the IEC port, too.
With the DTV you can use the 1541u in standalone mode (using IEC cable only). Only a few features are available then of course.
The 1541u support in the TRSI kernal is support for some 1541u-specific commands (telling it to open a D64 etc.).
BTW all this is available on the net on the common websites (for example the TRSI kernal README conveniently available directly on its download page).
Has someone made it possible to extract the expansion port pins off the DTV chip ??
There are no expansion port lines on the DTV chip.
Post by Espen Skog on Nov 17, 2008 15:05:56 GMT -5
Oh, that explains it. I did not know that the 1541u also had to be connected to the IEC on the c64. Now it all makes much more sense how the 1541u can be used with the DTV via the IEC only :-)
BTW: Do you know if someone has managed to make some kind of a freezer function on the DTV ? I mean, so that you can press a key combo or something, which lets you into a freeze-menu (like the Action Replay) where you can fiddle around just like on the C64... and then "exit" the freezer and return to the game/demo/prog ?
PS! Are the Cartridgeemulator-part of the 1541U available when it is only IEC connected to the DTV ?
Post by Espen Skog on Nov 18, 2008 13:16:23 GMT -5
Dude, I would die before I would admit to any limitations of the C64 :-)
However, is there no pin on the dtv which is possible to access somehow, that sends an irq or similar to the chip which can trigger something that launches something in c64 mode ? Are you completely sure ?
Last Edit: Nov 18, 2008 13:18:28 GMT -5 by Espen Skog
Do you know if someone has managed to make some kind of a freezer function on the DTV ?
A freezing function comparable to C64 freezer modules is not possible on the DTV. There's no way to transfer control to a certain code snipped by a keypress as is possible on the C64.
Actually there is an NMI, IRQ and DMA pin on the ASIC and we have full access to the memory it is executing from. This means some freezer-like functions could theoretically be constructed. It would require modifications to the DTV board though, probably major ones. Also I doubt the NMI line could be forced like on the c64.
Post by Espen Skog on Nov 18, 2008 16:13:13 GMT -5
Yeah, I would have though that the chip had external irq pins one could use. I mean, how if you poll the irq while the chip has power, and if it is triggered, one can take the memory in use by the DTV and dump it to a ram-chunk as a freeze-frame of what the c64 was doing. Then when you wants to resume, you copy back that data and resumes.
one can take the memory in use by the DTV and dump it to a ram-chunk as a freeze-frame of what the c64 was doing.
Getting a snapshot of the RAM is the easiest part. Reading the state of the emulated chips (CIAs, VICII, etc.) is the problem. And then there's also the problem with reading the state of extra DTV functionality (memmapper etc.).
If you want snapshots/freezes for faster starting of games, use VICEplus/x64dtv/vsfReanimator. If you want savegames, disassemble and patch the game in question to add this functionality.
Post by Espen Skog on Nov 19, 2008 12:15:02 GMT -5
Neup. I am not so much into games. However, it seems that e.g. a uIEC is the closest thing to a real 1541 when it comes to the DTV, and what I really want is a codeready DTV with IO options to the uIEC -- and also a friendly environment, just like one had with the ARMK6 and similar.
I wish, if Santa hears me, that a new batch of DTVs come out with expansion pins ;-) LIke, a forgotten batch in Asian, which never made it to the market. That would be a nice xmas gift, heh ;-)
hi Flashed the TRSI DTV Kernal v1.0 to $1FC000 to be used from DTVBOOT/DTVMON 1.2 at $1F8000. The kernal boots up ok trough dtvboot (pressing k) . The DTV engine board is started up in room temperature. When the DTV core ASIC warms up the DTV (TRSI kernal) starts resetting itself continuously. First Like pressing run/stop+restore faster and faster all the time.
Adding some cold spray around the ASIC and crystal area stabilizes the situation and TRSI DTV kernal boots up ok again.
The interesting point is that when TRSI kernal keeps resetting , the original DTV Kernal boot screen works OK ! (well patched the reset hook with TLR's kernalpatcher). Also all the games works without problems.
Now it comes to my mind if the crystal frequency starts to drift due the warming and TRSI kernal routines are somehow prone to the frequency error caused by that reason???
I have to try this also with the previous versions of peiselulli kernals
Also flash version of peiselulli kernal v0.4 behaves similar as TRSI v1.0. Still loadable .prg versions of both kernals work ok, without resets.
DTV's own power supply circuit was not good enough for flash version of TRSI kernel. With 5V input voltage the output dropped around 3.14 - 3.16V when normally it was 3.19 with other applications. Circuit now replaced with 3V3 linear regulator and now everything is working ok.
Now when the reset problem is finally tackled, the conclusion is that flash version seems to take more current than .prg version.