Mark90 Posted May 26, 2003 Report Share Posted May 26, 2003 Hi when I first power up the core I get the sysex F0 00 00 7E 40 00 01 F7 ;DOnly problem is that it is continuously sent over and over again, and am unable to get a reply to the sent message F0 00 00 7E 40 00 0F F7 :-/I Can t find any shorts on the board so any suggestions would be most welcome.I am also using a 5.7k resistor on the pic to optocoupler midi input as I am unable to obtain a 5.6k is this okay or do I need to locate a 5.6k resistor ! ??? Quote Link to comment Share on other sites More sharing options...
js Posted May 26, 2003 Report Share Posted May 26, 2003 I´ve tried the same prob ones. I´ve burned the bootloader to the pic again and then it worked fine.As for the resistor im not sure, but I can´t see how that should cause the problem you discribe.Good luck! Quote Link to comment Share on other sites More sharing options...
MrMusicman Posted May 26, 2003 Report Share Posted May 26, 2003 Hey Mark90Using a 5.7Kohm resistor on he optocoupler should not make any different,its only a pulldown resistor to control the intern current.(and only the MIDI input will not work).Kent Quote Link to comment Share on other sites More sharing options...
Mark90 Posted May 27, 2003 Author Report Share Posted May 27, 2003 I tried a new bootsrap and have just uploaded the mios operating system.All is working ;DThanks Quote Link to comment Share on other sites More sharing options...
Dr_Nick Posted May 28, 2003 Report Share Posted May 28, 2003 I'm experiencing the same problems with my MIDIbox SID.I allready had it up and running with a PIC16F877 and all I did change were the crystal and the PIC, so I guess I could rule out any hardware problems.I tried sending the firmware several times now, but the only thing that's send back is "F0 00 00 7E 40 00 01 F7" every 2 seconds.... I reprogrammed the PIC with the bootstrap loader, but that didn't help either.I'm using the PICstart plus programmer and noticed that the device ID only has 8 digits instead of the 16 that are shown in IC-Prog. Could that be part of the problem?Any help will be greatly appreciated!Dr. Nick Quote Link to comment Share on other sites More sharing options...
Steven_C Posted May 28, 2003 Report Share Posted May 28, 2003 So, why don't you erase the PIC, and upload the newest version of the bootstrap loader like Mark did??sorry if I've missed something, from Steve Quote Link to comment Share on other sites More sharing options...
Dr_Nick Posted May 28, 2003 Report Share Posted May 28, 2003 I'm allready using the latest version of the bootstrap loader (v1.1b). And I've tried erasing the PIC and reprogramming it several times now, but it still doesn't work....As I mentioned before, with the MPLAB ide (Microchip's development environment that ships with the PICstart plus programmer) the device ID is only 4 bytes long, instead of the 8 bytes shown on the bootstrap loader example page. So maybe I can't set the interface to the correct baud rate? Would a computer still be able to recieve the sysex messages if the baud rate was wrong while the PIC would fail to do so correctly?Dr. Nick. Quote Link to comment Share on other sites More sharing options...
TK. Posted May 30, 2003 Report Share Posted May 30, 2003 Hi Nick,you should see the device ID in the "Download request" SysEx message which is sent by the bootstrap loader immediately after power-on. If the PIC doesn't send any MIDI data, the reason must be somewhere else. I'm currently not able to check the IDE (cannot be started under Linux...) but I guess that the predefined settings in the .hex file will be programmed correctly into the configuration sector although they are not displayed. With the wrong baudrate you should receive invalid MIDI events (some Pitch Bender and controllers). Maybe it's better to start with the LED test first to check if the bootloader has been started:Best Regards, Thorsten.P.S.: is your board stuffed with a 20 MHz or 10 MHz crystal? Quote Link to comment Share on other sites More sharing options...
Dr_Nick Posted May 30, 2003 Report Share Posted May 30, 2003 I'm using a 10MHz crystal and I do see the download request in MIDIox. I've allready installed MIDI in and out LEDs on my selfmade board and the "in" LED shows MIDI activity while MIDIox is sending the sysex file. I've set up MIDIox as explained on the bootstrap example page (750ms delay, etc...).And as I wrote before, I allready got the whole thing up and running with a PIC16F877, with working MIDI-in and all. The only things I changed now are the PIC and the crystal.All the PIC18f452 does now is send the download request every 2 seconds (MIDI-out LED flashing and all...), even while I'm trying to upload the operating system. Any idea what I could be doing wrong? Quote Link to comment Share on other sites More sharing options...
Steven_C Posted May 30, 2003 Report Share Posted May 30, 2003 I'm probably stating the obvious, but remember that you have to send the sysex for the os within two seconds of receiving the dump request, after you turn the 'box on. Failing that, where are you located? if you have a spare pic, maybe you can post it so someone fairly local can load the os for you? good luck, from Steve Quote Link to comment Share on other sites More sharing options...
Dr_Nick Posted June 1, 2003 Report Share Posted June 1, 2003 I've already tried to programm the PIC with the lates SID firmware, but all I get when I turn the box on is a blank LCD and no reaction to any MIDI data... Then again I don't have the DIN module connected, so is the MIDIbox SID supposed to run without it? Quote Link to comment Share on other sites More sharing options...
TK. Posted June 1, 2003 Report Share Posted June 1, 2003 Hi Nick,I tried to upload the bootstrap loader with my PICstart plus and noticed the same. Unfortunately this is not the only bug in MPLAB (did the Microchip guys every test the PIC18F drivers?), however, you will find a workaround here:http://www.ucapps.de/mios/mios_bootstrap_picstart_workaround_v1.zipfrom the main.asm ; This program is a workaround for the PICstart programmer driver ; of MPLAB and MPLAB IDE - following bugs have been encountered: ; o the driver doesn't allow to write the complete ID field. ; Only 8 ID digits can be specified, although the PIC18F452 ; provides 16 digits (= 8 bytes) ; o the driver doesn't burn the whole firmware correctly when overwriting ; of the ID field has been disallowed under Programmer->Settings ; ; NOTE: !!! IC-Prog users don't need to run this program, since this ; !!! buring software writes the ID field correctly ; ; So, here are the required steps for a proper ID initialization: ; o burn the MIOS bootstrap loader into the PIC ; o load this project ; o change the ID settings for your needs in the code below ; (default: 0x0000000000000000) ; o assemble this program or just use the preassembled .hex file if you ; don't want to use a different ID ; o reconfigure the programmer so that only the first 4k block will be ; overwritten ; - MPLAB IDE: click on Programmer->Settings, change Program memory ; end address from 7fff to fff, ; thereafter click on Programmer->Program ; - MPLAB V5.4: click on PICStart Plus->Program Verify, set the end ; address from 0x7fff to 0xfff, ; thereafter click on the program button ; o plug the PIC into the core module, start the program ; -> the MIOS bootstrap loader will get active for 2 seconds ; -> thereafter this program will be started ; -> the MIOS bootstrap loader will be started again, but now with ; the correct ID settings ; o don't forget to set the "program end address" to 0x7fff again before ; you upload the bootstrap loader for another PIC Best Regards, Thorsten. Quote Link to comment Share on other sites More sharing options...
Dr_Nick Posted June 2, 2003 Report Share Posted June 2, 2003 Hi Thorsten!Using your workaround, everything is running without any problems! Thank you very much!!! Quote Link to comment Share on other sites More sharing options...
TK. Posted June 3, 2003 Report Share Posted June 3, 2003 great! :)Best Regards, Thorsten. Quote Link to comment Share on other sites More sharing options...
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