Zerosquare Posted June 16, 2007 Share Posted June 16, 2007 (edited) Here's a little idea I had to circumvent the Jaguar's UART bug. The ZIP file contains a detailed description and a demo program (the source code is included). It's available in this post on Jagware (no registration required). Enjoy ! Edited June 17, 2007 by Zerosquare Quote Link to comment Share on other sites More sharing options...
Matthias Posted June 16, 2007 Share Posted June 16, 2007 Hello! Here's a little idea I had to circumvent the Jaguar's UART bug. The ZIP file contains a detailed description and a demo program (the source code is included). Thanks for sharing this The idea sounds interesting, and to be honest i didn't know about the described option to read the data-stream while avoiding to use the receiver. I have just tested the example program, it works as described (although the blank black screen on the Jaguar irritated me first), but sadly sending a stream of data shows the drop-outs as described in the README.TXT, but the positive thing is, that the Jaguar never crashed when receiving the stream (i sent 800 ASCIIs using Hyperterminals "Send Text-file"-option). What i really like in this approach is, that everything is done inside the (receiving) Jaguar, no need to change the serial transmission itself (like using more or less STOP-bits, or sending the data-bytes spread over more than just 8 serial-data-bits). Kind regards Matthias Quote Link to comment Share on other sites More sharing options...
Zerosquare Posted June 16, 2007 Author Share Posted June 16, 2007 I'm glad you like it. The drop-out problem can be easily fixed by implementing a buffer, it's just that I was too lazy to code it (same thing for the black screen) Quote Link to comment Share on other sites More sharing options...
Matthias Posted June 16, 2007 Share Posted June 16, 2007 Hi! I'm glad you like it. The drop-out problem can be easily fixed by implementing a buffer, it's just that I was too lazy to code it (same thing for the black screen) Don't be so lazy, post a second example with a buffer tomorrow BTW: The "MAKEFILE" in your ZIP is more like a DOS-Batch-file, i renamed it to "M.BAT" in my environment. Regards Matthias Quote Link to comment Share on other sites More sharing options...
Gorf Posted June 17, 2007 Share Posted June 17, 2007 Here's a little idea I had to circumvent the Jaguar's UART bug. The ZIP file contains a detailed description and a demo program (the source code is included). Enjoy ! All the interesting code runs on the DSP ; the 68000 is only used as a bootstrap, then stopped immediately after so it doesn't hog the bus (maybe that's not really necessary, but hey Amen to that..it is nice to see others using coding practices like this on the jag. Good work. that is how it should be. Nice work! Quote Link to comment Share on other sites More sharing options...
Zerosquare Posted June 17, 2007 Author Share Posted June 17, 2007 Thanks, Gorf. Quote Link to comment Share on other sites More sharing options...
SebRmv Posted June 17, 2007 Share Posted June 17, 2007 Thanks for sharing this, Zerosquare! Quote Link to comment Share on other sites More sharing options...
Zerosquare Posted June 17, 2007 Author Share Posted June 17, 2007 Well Matthias, I listened to you Version 1.01 is ready. It can be downloaded by clicking on the link in the first post of this topic. Here are the changes : - Fixed a few bugs - Fixed the "dropped characters" issue (by adding a 1 MB circular buffer... I hope it's enough for you ! ) - Made the screen green (see ? no more black screen ) - Renamed Makefile to Makefile.bat (you were right, it's actually a batch file) Oh, and I've credited you in the changelog as well I've made a few tests by transferring a ~100 kB text file several times(and temporarily disabling the "add one to the character" to get a readable echo), it seems that no characters get dropped or corrupted. Quote Link to comment Share on other sites More sharing options...
JagChris Posted June 18, 2007 Share Posted June 18, 2007 This is nice to see other developers actually tackling this problem. Good stuff. Quote Link to comment Share on other sites More sharing options...
viMaster Posted June 18, 2007 Share Posted June 18, 2007 Wow. It's great that someone else has been able to find a possible workaround that could be used for future development. ... and to make the findings available to everyone is definitely a great thing and will hopefully inspire someone to make optimizations and changes to make it fully usable Quote Link to comment Share on other sites More sharing options...
Pocket Posted June 18, 2007 Share Posted June 18, 2007 Nice work Zero, thanks for sharing your work to everyone Quote Link to comment Share on other sites More sharing options...
Matthias Posted June 18, 2007 Share Posted June 18, 2007 Hello Zerosquare! Well Matthias, I listened to you Version 1.01 is ready. It can be downloaded by clicking on the link in the first post of this topic. Ok, thanks :-) Kind regards Matthias Quote Link to comment Share on other sites More sharing options...
TXG/MNX Posted June 18, 2007 Share Posted June 18, 2007 when to see a fix for doom ? Quote Link to comment Share on other sites More sharing options...
Zerosquare Posted June 18, 2007 Author Share Posted June 18, 2007 when to see a fix for doom ? I was waiting for someone to ask this I'm not interested in DOOM myself, but if anyone wants to do it, I can help. Quote Link to comment Share on other sites More sharing options...
belboz Posted June 19, 2007 Share Posted June 19, 2007 How fast have you been able to get the software UART to be reliable at? I did a software UART on the Jag a couple years ago when flirting with my serial based download program (a CD based JUGGS). I was able to get 19200 and 38400 baud working well enough with the software UART. I dropped the idea because I had no problems with 38400 and slower on the built in Jag serial port, so I didn't see the value in a software UART that wasn't getting me any faster speeds. Plus for my serial download application I wanted 115200. Quote Link to comment Share on other sites More sharing options...
Zerosquare Posted June 19, 2007 Author Share Posted June 19, 2007 How fast have you been able to get the software UART to be reliable at?For the moment, I only tested my code at 9600 bps to verify that the implementation was working okay... The maximum speed would depend on how many cycles per second you'd allocate to the software UART, of course. I did a software UART on the Jag a couple years ago when flirting with my serial based download program (a CD based JUGGS).Were you involved in the original JUGS, or did you reverse-engineer the protocol ? I dropped the idea because I had no problems with 38400 and slower on the built in Jag serial portThat's very interesting ! So you found a way to avoid the UART bug too ? Quote Link to comment Share on other sites More sharing options...
Tempest Posted June 19, 2007 Share Posted June 19, 2007 Anyone want to share with us non-Jag programmers exactly what the UART bug is? From what I can gather it has something to do with the networking code. That would explain why Doom flakes out during deathmatches half the time. Tempest Quote Link to comment Share on other sites More sharing options...
Zerosquare Posted June 19, 2007 Author Share Posted June 19, 2007 Anyone want to share with us non-Jag programmers exactly what the UART bug is? From what I can gather it has something to do with the networking code.Yes, the UART is the part of the Jaguar chipset which handles the networking. Due to a design error, it tends to malfunction and lock up, which halts the communication between consoles. There is a workaround mentioned in Atari's developers documentation, but it seems that it is not sufficient to avoid all problems. Quote Link to comment Share on other sites More sharing options...
Zerosquare Posted June 19, 2007 Author Share Posted June 19, 2007 BTW, just did some testing : my code seems to work fine at 115,200 bps. Quote Link to comment Share on other sites More sharing options...
belboz Posted June 19, 2007 Share Posted June 19, 2007 Were you involved in the original JUGS, or did you reverse-engineer the protocol ? No. My protocol was my own. I was going to release the software on my website for a BJL alternative for the masses. That's very interesting ! So you found a way to avoid the UART bug too ? I would say I was able to avoid most bugs as long as I stayed at or below 38400. Biggest thing I found was that it looked like no matter what you always got even or odd parity with the jag. I noticed when I configured my PC accordingly I could send large packets to the Jag no problem. As you mentioned sending from the Jag was no problem regardless. Once I made sure I had the parity right (even or odd depending on how I configured the jag, and never set to none) things worked great. I did follow the info in Atari dev docs also when it came to avoiding the bug they mention. I pretty much had rock solid 38400 and below after doing the above. Since you mentioned your code works at 115200 I will have to give my download CD another go. Quote Link to comment Share on other sites More sharing options...
walter_J64bit Posted June 20, 2007 Share Posted June 20, 2007 (edited) WOW, we might have working deathmatches for DOOM! Edited June 20, 2007 by walter_J64bit Quote Link to comment Share on other sites More sharing options...
Gorf Posted June 20, 2007 Share Posted June 20, 2007 Anyone want to share with us non-Jag programmers exactly what the UART bug is? From what I can gather it has something to do with the networking code. That would explain why Doom flakes out during deathmatches half the time. Tempest Its a real cheap UART that they put in there and they never bothered to debug it. IT completely locks up the Jaguar to the point where you have to reboot. There are workarounds being developed other than the current ones that exist. Quote Link to comment Share on other sites More sharing options...
viMaster Posted June 20, 2007 Share Posted June 20, 2007 Anyone want to share with us non-Jag programmers exactly what the UART bug is? From what I can gather it has something to do with the networking code. That would explain why Doom flakes out during deathmatches half the time. Tempest There are workarounds being developed other than the current ones that exist. The more the merrier! Quote Link to comment Share on other sites More sharing options...
Tempest Posted June 20, 2007 Share Posted June 20, 2007 Its a real cheap UART that they put in there and they never bothered to debug it. Atari Corp. cheap? Never! Tempest Quote Link to comment Share on other sites More sharing options...
TXG/MNX Posted June 23, 2007 Share Posted June 23, 2007 Were you involved in the original JUGS, or did you reverse-engineer the protocol ? No. My protocol was my own. I was going to release the software on my website for a BJL alternative for the masses. That's very interesting ! So you found a way to avoid the UART bug too ? I would say I was able to avoid most bugs as long as I stayed at or below 38400. Biggest thing I found was that it looked like no matter what you always got even or odd parity with the jag. I noticed when I configured my PC accordingly I could send large packets to the Jag no problem. As you mentioned sending from the Jag was no problem regardless. Once I made sure I had the parity right (even or odd depending on how I configured the jag, and never set to none) things worked great. I did follow the info in Atari dev docs also when it came to avoiding the bug they mention. I pretty much had rock solid 38400 and below after doing the above. Since you mentioned your code works at 115200 I will have to give my download CD another go. Will you release your version of aswell? All extra info would be nice... Quote Link to comment Share on other sites More sharing options...
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