Jump to content
ajacocks

1541U2+ Doesn't Work on C64 Reloaded Mk2

Recommended Posts

All,

I'm not sure that this would be considered a supported config, but I have heard that the 1541 U2/U2+ work on C64 Reloaded boards. However, this does not seem to be the case, with my Reloaded Mk2 board and my 1541 U2+.

I'm running firmware 3.2, and have tried 3.2a, and both seem to work about 75%, as far as accessing the cart's config and loading menus. Sometimes, you get a corrupted screen when hitting the menu button, or other functions.

Once you try to mount or run an image, however, no disk is seen by the C64. Loading "$" or any program on disk results in a "?FILE NOT FOUND ERROR", and neither the lights nor the sound are heard from the 1541U2+.

Has anyone else here tried this? Is there any debugging information that I can collect, that might be helpful? I have tried 2 different 12VDC PSUs, so I don't think that's the issue. My 1541U2+ seemed to work perfectly on my 128D, last time that I tried it.

Thanks!
- Alex

Edited by ajacocks

Share this post


Link to post
Share on other sites

I got nothing useful for you on this one, other than making sure you have the latest firmware for the Reloaded, as well.

Share this post


Link to post
Share on other sites

All,

 

I'm not sure that this would be considered a supported config, but I have heard that the 1541 U2/U2+ work on C64 Reloaded boards. However, this does not seem to be the case, with my Reloaded Mk2 board and my 1541 U2+.

 

I'm running firmware 3.2, and have tried 3.2a, and both seem to work about 75%, as far as accessing the cart's config and loading menus. Sometimes, you get a corrupted screen when hitting the menu button, or other functions.

 

Once you try to mount or run an image, however, no disk is seen by the C64. Loading "$" or any program on disk results in a "?FILE NOT FOUND ERROR", and neither the lights nor the sound are heard from the 1541U2+.

 

Has anyone else here tried this? Is there any debugging information that I can collect, that might be helpful? I have tried 2 different 12VDC PSUs, so I don't think that's the issue. My 1541U2+ seemed to work perfectly on my 128D, last time that I tried it.

 

Thanks!

- Alex

 

I see you mentioned you used it previously on a 128, did you change the timing settings etc with it? There is this note on the Reloaded MK2 wiki:

 

"When using the 3.x firmware make sure the timing parameters are at their default values (CPU Addr valid after PHI2: 80ns-96ns depending on firmware, PHI2 edge recovery: Enabled)."

 

I only have a 1541 Ultimate II (not the latest) but I did have to make some changes myself to get it running on my 128.

Share this post


Link to post
Share on other sites

Thanks, sm3. I actually managed to get the II+ to be stable, by reducing the PHI2 to ~64ns and disabling PHI2 edge recovery.

 

However, I still get the “?FILE NOT FOUND ERROR” on all .d64 files. Also, I never see the access or error lights come on, on the cartridge, suggesting to me that the C64 isn’t actually requesting a disk.

 

I seem to remember that the IEC port is controlled by the 6522 chip. The reloaded board doesn’t have a 6522, just the 6510, 2 CIAs, a VIC-II, and a pair of SIDs. I’m wondering if one of my chips is partially bad.

 

I’d love to test with a real floppy drive, but I gave away my external drives, since the 1571 in my 128DCR works fine. I’m on the lookout for a localish drive, and I ordered an SD2IEC.

 

- Alex

Share this post


Link to post
Share on other sites

Thanks, sm3. I actually managed to get the II+ to be stable, by reducing the PHI2 to ~64ns and disabling PHI2 edge recovery.

 

However, I still get the “?FILE NOT FOUND ERROR” on all .d64 files. Also, I never see the access or error lights come on, on the cartridge, suggesting to me that the C64 isn’t actually requesting a disk.

 

I seem to remember that the IEC port is controlled by the 6522 chip. The reloaded board doesn’t have a 6522, just the 6510, 2 CIAs, a VIC-II, and a pair of SIDs. I’m wondering if one of my chips is partially bad.

 

I’d love to test with a real floppy drive, but I gave away my external drives, since the 1571 in my 128DCR works fine. I’m on the lookout for a localish drive, and I ordered an SD2IEC.

 

- Alex

 

Ah, well you are getting closer! Perhaps we are just overlooking something simple. I use a Turbo Chameleon with my MK2 unfortunately, so I can't reproduce what you are experiencing.

 

One thing that came to mind, you have the 1541 ROM installed on your SD card right? It's easy to overlook that.

Share this post


Link to post
Share on other sites

One thing that came to mind, you have the 1541 ROM installed on your SD card right? It's easy to overlook that.

What do you mean? AFAIK, you don’t need to have a 1541 ROM on your SD card/thumb drive, unless you’re using a non-stock (not 1541/1541-C/1541-II) ROM. Am I wrong?

 

- Alex

Share this post


Link to post
Share on other sites

I'm not sure that this would be considered a supported config, but I have heard that the 1541 U2/U2+ work on C64 Reloaded boards

 

I've used my 1541 U2+ extensively with my C64 Reloaded Mk2 without issues.

Share this post


Link to post
Share on other sites

What do you mean? AFAIK, you dont need to have a 1541 ROM on your SD card/thumb drive, unless youre using a non-stock (not 1541/1541-C/1541-II) ROM. Am I wrong?

 

- Alex

Yeah, probably right, I've never used mine without JiffyDOS so you put the drive and OS ROMs on the Ultimate SD/USB. But mine sits in the closet unused these days ;)

Share this post


Link to post
Share on other sites

Ah, I see. What do you use, instead?

Turbo Chameleon 64. Before I had a Reloaded MK1 or MK2 I used the Ultimate on my real 64C and used the kernal ROM replacement feature (of the Ultimate II) so I didn't need to install JiffyDOS ROM on my 64C.

Share this post


Link to post
Share on other sites

Interesting. What do you like better about the TC?

I originally purchased it because of the VGA output, which I don't use since I have a great Sony PVM, but it's there if I need it.

 

I supposed the one thing I really like about the Turbo Chameleon is no IEC cable needed.

Share this post


Link to post
Share on other sites

The 6522 runs the serial bus on the VIC-20. These are replaced by the 6526 and 8521 in the C64 and C128. The 1541 and 1571 still use the 6522 for the serial bus.

Share this post


Link to post
Share on other sites

Yep, and this was the problem. I didn't notice, but one of the CIAs was installed backwards.

 

Thanks for the suggestion, OLD CS1. You got me thinking in the right direction.

 

- Alex

Share this post


Link to post
Share on other sites

Yep, and this was the problem. I didn't notice, but one of the CIAs was installed backwards.

 

Thanks for the suggestion, OLD CS1. You got me thinking in the right direction.

 

- Alex

 

So it's working now? Did the LED on the PCB give you an error state? I think it's supposed to also give you more information if you connect to the USB on the board if there is an error. I didn't even think to consider the chips you installed.

Share this post


Link to post
Share on other sites

Yeah, there was no debug information in the management interface of the C64 Reloaded, because it doesn't really examine the CIAs. It does detailed checks on the 6510, VIC-II and SIDs, which were all working.

 

Just a silly problem, and I should have noticed sooner. I'm glad that being installed backwards didn't fry my CIA.

 

- Alex

Share this post


Link to post
Share on other sites

Yeah, there was no debug information in the management interface of the C64 Reloaded, because it doesn't really examine the CIAs. It does detailed checks on the 6510, VIC-II and SIDs, which were all working.

 

Just a silly problem, and I should have noticed sooner. I'm glad that being installed backwards didn't fry my CIA.

 

- Alex

 

Nice! I'm glad you still have a working CIA too.

Share this post


Link to post
Share on other sites

 

I've used my 1541 U2+ extensively with my C64 Reloaded Mk2 without issues.

 

Same here. My 1541 U2+ worked right out of the box with my Reloaded Mk2 with no problems. Glad you sorted it out!

 

The only thing I have found that causes 'Issues' on the MK2 is the Wimodem as it sends 5v pulses that cause display interference.

Edited by Arnuphis

Share this post


Link to post
Share on other sites

The only thing I have found that causes 'Issues' on the MK2 is the Wimodem as it sends 5v pulses that cause display interference.

 

That's a myth. There are no "pulses" sent by the WiModem. The problem is with the C64Reloaded's 8701 replacement circuitry. It is too sensitive to changes in the 5 volt rail. The exact same problem exists with the C64Reloaded Mk1 board *if* you use the fake 8701 board. If you use a real 8701 with the C64Reloaded Mk1 board there are no issues. Likewise, if you put the fake 8701 board into a C64 you will then have the issues. Also, if try to use several other user port devices, such as Jason Ranheim's EPROM programmer, the PP64 EPROM programmer, or the Covox Voicemaster with the fake 8701 board or the C64Reloaded Mk2 board, you will also have the exact same issue that is seen with a WiModem.

 

So... let's recap:

 

C64Reloaded Mk1 board with fake 8701 and WiModem, EPROM programmer, or digitizer = video artifacts

C64Reloaded Mk 1 board with real 8701 and WiModem, EPROM programmer, or digitizer = perfect video

C64Reloaded Mk2 board with WiModem, EPROM programmer, or digitizer = video artifacts

C64 with fake 8701 and WiModem, EPROM programmer, or digitizer = video artifacts

C64 with real 8701 and WiModem, EPROM programmer, or digitizer = perfect video

Edited by JimDrew

Share this post


Link to post
Share on other sites

 

That's a myth. There are no "pulses" sent by the WiModem. The problem is with the C64Reloaded's 8701 replacement circuitry. It is too sensitive to changes in the 5 volt rail. The exact same problem exists with the C64Reloaded Mk1 board *if* you use the fake 8701 board. If you use a real 8701 with the C64Reloaded Mk1 board there are no issues. Likewise, if you put the fake 8701 board into a C64 you will then have the issues. Also, if try to use several other user port devices, such as Jason Ranheim's EPROM programmer, the PP64 EPROM programmer, or the Covox Voicemaster with the fake 8701 board or the C64Reloaded Mk2 board, you will also have the exact same issue that is seen with a WiModem.

 

So... let's recap:

 

C64Reloaded Mk1 board with fake 8701 and WiModem, EPROM programmer, or digitizer = video artifacts

C64Reloaded Mk 1 board with real 8701 and WiModem, EPROM programmer, or digitizer = perfect video

C64Reloaded Mk2 board with WiModem, EPROM programmer, or digitizer = video artifacts

C64 with fake 8701 and WiModem, EPROM programmer, or digitizer = video artifacts

C64 with real 8701 and WiModem, EPROM programmer, or digitizer = perfect video

 

So to sum up putting a Wimodem in a MK2 causes display issues, which is what I said. I stand corrected on the 'pulses' but it's not a myth as you just illustrated.

Share this post


Link to post
Share on other sites

Apparently using any user port device that requires power with the Mk2 cause the same display issue, not just the WiModem.

Edited by JimDrew

Share this post


Link to post
Share on other sites

Apparently using any user port device that requires power with the Mk2 cause the same display issue, not just the WiModem.

 

hrmmm that is a bummer. Have my MiniModem C24 sitting here waiting for use :/

Share this post


Link to post
Share on other sites

If you isolate pin 2 on the user port from the user port device, you can supply a separate 5v supply to device (along with ground of course) and that will resolve the issue. As long as the Mk2 is not supplying the +5v to the user port device then there are no video issues.

Edited by JimDrew

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...

  • Recently Browsing   0 members

    No registered users viewing this page.

×
×
  • Create New...