Search found 44 matches

by amushrow
Sat Dec 29, 2018 7:08 pm
Forum: Demos
Topic: CVSD Compressed audio example
Replies: 74
Views: 25211

Re: CVSD Compressed audio example

Thanks for those Chilly Willy, I think the stuff I've been working on sounds cleaner for the same file sizes so I'm going to continue on with that. Hopefully I can get it running on an actual console in the next few days and get some real world comparisons. Then I can stop thinking about it and do s...
by amushrow
Fri Dec 28, 2018 2:26 am
Forum: Demos
Topic: CVSD Compressed audio example
Replies: 74
Views: 25211

Re: CVSD Compressed audio example

Revivification! I've been using my free time over Christmas to work on some software stuff before I'm extra busy again in January and have been looking into audio compression for on the MD. After a while I came across this stuff, unfortunately all the fileden links are dead so I've not been able to ...
by amushrow
Sat Jun 30, 2018 11:48 pm
Forum: UMDK
Topic: Coming Soon(ish)... probably [Update - 15/06]
Replies: 8
Views: 5136

Re: Coming Soon(ish)... probably [Update - 15/06]

These would be completed kits with everything already soldered together, tested and with the UMDK firmware installed. I've already soldered together the LX9 boards, and I just need to gold plate the pins on the rest of the bridge boards before I solder the components onto them. I'll have to work out...
by amushrow
Sun May 20, 2018 6:07 pm
Forum: UMDK
Topic: Coming Soon(ish)... probably [Update - 15/06]
Replies: 8
Views: 5136

Coming Soon(ish)... probably [Update - 15/06]

Time to sell off all my extra boards and parts for the UMDK, but I can't sell boards by themselves they'd need a box to keep them safe, and it's really awkward to get the UMDK in and out of the Mega Drive without a cartridge shell so it should have one of those too right? UMDK I'll probably have 8 o...
by amushrow
Wed Feb 28, 2018 11:09 am
Forum: UMDK
Topic: How to build firmware (UMDK Menu + Monitor)?
Replies: 5
Views: 2323

Re: How to build firmware (UMDK Menu + Monitor)?

Yeah bad connection (between the MD and the cart) And then I started getting some other weird errors, the result being I've bought a bunch of bad cypress usb chips and it seems I was lucky that this one worked at all (for a while anyway). Everything I go to look at recently isn't working right (not ...
by amushrow
Tue Feb 13, 2018 10:24 am
Forum: UMDK
Topic: UMDK Manufacturers?
Replies: 1
Views: 975

Re: UMDK Manufacturers?

I don't think anybody is actually producing them, in the past if enough people wanted one then they would organise for a batch of them to be ordered.
I might have a few to sell at some point (made up of all the spare bits I've got) but I couldn't commit to a date.
by amushrow
Sat Jan 20, 2018 1:47 pm
Forum: UMDK
Topic: How to build firmware (UMDK Menu + Monitor)?
Replies: 5
Views: 2323

Re: How to build firmware (UMDK Menu + Monitor)?

I feel like this is working against me. Still having trouble loading roms (most of the time), and can't connect the debugger. It seems that there is some memory mapping issue, or something. The monitor is loaded at 0x400000, the menu program stores filenames and whatnot starting at 0x440000, the pro...
by amushrow
Tue Jan 16, 2018 11:16 pm
Forum: UMDK
Topic: How to build firmware (UMDK Menu + Monitor)?
Replies: 5
Views: 2323

Re: How to build firmware (UMDK Menu + Monitor)?

Oh for goodness sake: main.c void doSelect(struct FileSystem *fs, s16 choice) { ... const u16 clustersPerStar = (u16) (length / (32 * clusterLen)); ... for (i = 0; i < clustersPerStar; i++) { //read from sd card } VDP_drawText("*", x, 26); //Draw loading bar ... } The cluster size on the high capaci...
by amushrow
Mon Jan 15, 2018 11:29 pm
Forum: UMDK
Topic: How to build firmware (UMDK Menu + Monitor)?
Replies: 5
Views: 2323

Re: How to build firmware (UMDK Menu + Monitor)?

Compiling against the same version of SGDK that was originally used gets everything working, although the makefile needs to be updated (on windows at least) otherwise you don't get the link time optimisation and the firmware will be too big. I'm not sure what changed in SGDK that breaks it. I know t...
by amushrow
Sun Jan 14, 2018 11:15 pm
Forum: UMDK
Topic: How to build firmware (UMDK Menu + Monitor)?
Replies: 5
Views: 2323

How to build firmware (UMDK Menu + Monitor)?

I've made changes to the umdk menu program to support SDHC cards (so you can use cards up to 32GB). It works when I send it over using loader, but I only ever get a blank screen when I combine it with the monitor program (cat monitor.bin menu.bin > firmware.bin) and load it on to the umdk's flash. T...
by amushrow
Wed Jan 10, 2018 11:20 pm
Forum: UMDK
Topic: MD hangs after playing any PCM file
Replies: 69
Views: 14107

Re: MD hangs after playing any PCM file

I put together an original bridge board and the fix works on that too, hooray! (and also boo, it took ages to route that board in whatever program I used)

I just tried SSF2:TNC and it seems to work fine.
by amushrow
Wed Jan 10, 2018 9:42 pm
Forum: UMDK
Topic: MD hangs after playing any PCM file
Replies: 69
Views: 14107

Re: MD hangs after playing any PCM file

I checked on a regular Sonic 1 cart, there's a 190ns delay between that address line going low and the data lines being driven. With the change the UMDK has 135ns before driving the lines (before it was 105ns). I'd guess that something on the original MD isn't as quick as the UMDK and it wasn't read...
by amushrow
Wed Jan 10, 2018 9:26 pm
Forum: UMDK
Topic: MD hangs after playing any PCM file
Replies: 69
Views: 14107

Re: MD hangs after playing any PCM file

In the main UMDK firmware, in the memory arbiter. I've looked into it a little more this evening, it seems that waiting an extra cycle after mdAddr_sync(22) = '0' before driving the bus keeps the Mega Drive happy. In my case the final minimalist change was to replace add an extra state into the S_RE...
by amushrow
Tue Jan 09, 2018 10:53 pm
Forum: UMDK
Topic: MD hangs after playing any PCM file
Replies: 69
Views: 14107

Re: MD hangs after playing any PCM file

So whenever I get near the end of a project (or video game, or most things) I get distracted by something else and then it's an age before I get back into it. But I finally have an update. The pcb I designed with zener diodes to limit the voltages going to the fpga works a treat, signals are much le...
by amushrow
Tue May 02, 2017 4:18 pm
Forum: UMDK
Topic: MD hangs after playing any PCM file
Replies: 69
Views: 14107

Re: MD hangs after playing any PCM file

Jorge Nuno wrote:I'm pretty sure this bus abnormality is not there in normal cases.
I have observed the address lines holding at 1.5v on a regular cart too. The MDII doesn't display the same behavior.