MiSTer FPGA Forum

I went ahead and did a test. In the normal setup I can drive an SPI with approx 150kHz which is roughly 15KB/second including some overhead to a SPI USB interface. After changing sys_top into outputting real 1’s and 0’s I do 2Mhz or around 200KB/sec. So changing this creates at least 12 times the bandwidth. I guess driving Z’s in stead of 1’s was c...

When you drive 1's and 0's to the USER_IO port the signals are respectively high-Z and GND. This means that you need to use a pull-up resistor to pull high-Z to 3.3V. And because of parasitic capacitance on the IO board this means the serial bandwidth is limited to 150kHz. Why not drive real 1's instead? Is is okay to replace the following in sys_t...

Hi Olekk, I am currently implementing SPI via UserIO for the MSX core. I found out that the standard IO boards only allow around 200khz SPI clocks. This is due to the 10k pull-ups and the fact that the port is configured to do zero and Z and not zero and one. I am thinking about creating a different IO board that solves the former. The latter has t...

@bellwood420, I confirm it also works on my SPDIF capture card which was the reason for my initial fix. Looks like we're now entirely within the standard.

Yes. It looks like to ES9038 reads all the bits in the Spdif stream and shows it in one of its registers. So it should support the enabled bits as part of my fix. I wish I had one of these boards to check it for myself. I’ll continue to search for a solution.

Atohmdiy wrote: ↑Wed Feb 10, 2021 5:34 pm I don't know if the dac handle the spdif by itself or if they use an IC.

I think the left top IC is doing the I2S and Toslink conversion. The photo of the product page does not show the type number clearly. Can you check the product code on the IC?

This is the fact although I feel it is strange behavior(Is there a device not allowing to play music without copyright?) That is strange indeed. Did we also try just with the copy-bit? And leave the L-bit and sample-rate bit zero? In other posts on this forum I also saw other users being surprised that Toslink started to work for them suddenly aft...

I recently made a fix for Toslink that is being propagated to all cores. Glad it worked for you!

Hi Atohmdiy, As the author of the Spdif fix I want to help. Can you describe which setup you have? Where does your Toslink go to? The fix that I proposed was to correctly set the sample rate and the copy bit in the Spdif stream. Maybe you have hardware that is sensitive to this. Maybe I can for example remove the sample rate fix but leave the copy ...

I'm sure I must be missing something but just can't figure out what it is. Anyone able to help? I just start MultiComp. Then start a SSH to mister: ssh root@mister.lan. Then type minicom without any extra options and it should connect. Oh yeah, make sure that UART mode is None. Press SPACE for the MultiComp monitor to assign the serial connection ...

Aberu, thanks for your reply. I guess what I wanted to say is that standard USB3.0 type A male/male cables icw IO board make USER_IO[3] always 0. So you have to be careful when you think you can output signals because they will be pulled to ground. There is a pull/up and resistor in series in the IOboard so I don't think the Mister will be damaged....

I have the following setup: Digital IO board 1.2 USB3.0 Type A male to male cable an SPI board linked to USER_IO[2] SCK, USER_IO[3] MISO, USER_IO[4] MOSI, USER_IO[5] CS I checked with my oscilloscope that all signals reach the SPI board but that information is not send back because USER_IO[3] is held down to GND. The reason is the following: The ca...

I noticed that MiSTer emits S/PDIF audio frames with all status bits zero. According to the specification this leads to SCMS copy protection enabled, original recording flag being off and audio being reported as 44.1kHz. http://neximus.com/wp-content/uploads/2021/01/record_no.png In my case this meant that my USB sound card was unable to capture th...

jca wrote: ↑Sat Jan 02, 2021 11:08 pm I can post the rbf if the S0urceror gives me the green light.

Yes, no problem, please go ahead.

I am interested on learning how to build the core as there is no rbf. Can you confirm the Quartus version to be used (17 if I remember)? What do I have to download from Github and start the build? Thanks Download or clone everything from here: https://github.com/MiSTer-devel/MultiComp_MiSTer . Then start Quartus 17. Open MultiComp.qpf (project fil...

@Ron, I checked your core and it looks great!

Also took the liberty to merge your sd_controller.vhd with my version of MultiCore and it looks like it is working. But I think more testing is needed. If you check my GitHub you'll find the new code to build in Quartus. Let me know how it works on your side.

Okay, got it working. There was a problem with my design. USER_OUT/IN work as expected. Visible on Logic Analyser both direct and via 5v level shifter.

Is this for the Z80 core only? What kind of disk images (8MB HD)? Yes I made the changes for Z80 CP/M. I'll upload the software changes to my GitHub https://github.com/S0urceror/MultiComp_MiSTer/tree/master/Z80%20CPM%20and%20bootloader%20(basmon) . This should get things working on .VHD images. Instructions on installation can be found here: http:...

I guess you’re right! This explains the behavior I’m seeing. I’ll insert pull-ups and try again. Update: No, doesn't change anything. I also saw that the pins are already configured to have weak pull-ups. Btw. if I move slide-switch [1] in the ON position I do see HDMI_LRCLK on USERIO[5]. Only my own signals never appear when I put the slide-switch...

All, I am developing a core that uses USERIO. Somehow, and I checked with a Logic Analyser, I cannot get the signals to appear on P7 pins 0,1,4,5,6,7 and 9. I tried to understand what sys_top.v does. I understand that when I leave all slide switches in the OFF state the USERIO should appear. In my case all driven signals stay 0. I connected a simpl...

Update, after inserting a small wait (loop from 50 to 0) between the IN (check status) and OUT (write new block) in assembly code I managed to get a stable write. I was able to format a new disk and install CP/M on it. So I guess there is an issue with the virtual SD card implementation in the MISTer in combination with the MultiCore SD card contro...

Did you try the write on the disk image? it is not working for me please look this old post: https://www.atari-forum.com/viewtopic.php?p=366655#p366655 As a matter of fact I haven't done a write yet. I'll try and report back here. If there is a problem I'll fix that. Update : small writes work, like ERA TEXTFILE removes the TEXTFILE from the direc...

I decided to give the MultiComp a little bit of love and have updated it to the latest IP and sys files. I then added the ability to use image files that you can now put in the GAMES/MULTICOMP folder. Last but not least I added the UART functionality so that you can interface with MultiComp via the linux shell and minicom. Easier when you want to c...