kpete

I think I crashed it yesterday evening.

I don't know whats going on here but it looks like I may be crashing the forum server. The last time I did this I checked that the server was up and running OK. I then go to my local TRUNK directory on my C: drive then right click and select TortoiseSVN->Repo-browser and use the URL link of svn://svnmios.midibox.org/mios32 and the browser window is displayed with a message of “â€Please wait while the repository browser is initializingâ€. It then times out after about 1-2 minutes with an error. After doing this the http://midibox.org/forums/ link doesn't work anymore. I am working with a PC running Windows 7 64 bit. Something that I do remember: I was running with an old version of SVN when I created the TRUNK on the C: drive on Jan 14, 2013. About 2 weeks later I then updated to the latest TortoiseSVN software. After compiling the Midio128 V3 software, I find that my compiled version of the .HEX file is having issues connecting up to MIOS STUDIO. Looks like problems with the change from 2 port to 4 port Midi support (Boot loader version problem). So now I want to update my TRUNK with the latest changes which I can't do due to the server crashing. Has anyone heard of or seen this type of problem before or is it just a coincidence? Pete

Boy, I don't know if this issue is fixed or not from the posts being bounced back and forth. But I suspect it hasn't been fixed. I am surprised that nobody has asked to measure the AC voltage across the rectifier as seen on post #11. This should be a strong 30vac. If its not, then you have one of the polarities of the 2 ac transformers wired backward. When I say backwards I mean switch the 2 black wires on only one of the transformers. I suspect that you are seeing only a half wave rectified DC voltage from the bulk supply which will drop drastically under load rather than a full wave one. Pete

If all of your tracks being played from the Media player are Midi, you might just build a hand held Midi player using the MIDIO128 V3 project at http://www.ucapps.de/midio128.html. All the songs could be saved on the SD card of the hand held unit and 3 buttons (Soft 1,2,3) could be used to select the song and start and stop playing. The 20x2 LCD display would show the song title and you could even include an encoder for changing the tempo. It would send the data over the Midi1 out connector. You could even use the unused 2 pins on the connector to deliver power to the electronics of the hand held unit. Pete

I know that using the MIDI1 port to load the new boot loader does work. Had to do it myself because of a screw up on my part. I didn't have to do any deinstall's to get everything working again. Pete

It sounds like you will be using only Note ON/OFF events so you shouldn't have any problem with controlling the outputs. My comment about <63 relates to how Midtizer software uses CC events to control LED's for stop control. Pete

Hi Antonio, I am curious as to what you want to control? I can't answer how important it is to terminate the last input shift register to ground. I do know that I wrote software for this CORE and I didn't do this even though I used a Din board for my 14 push buttons. It doesn't make sense to me but maybe others will know about the reason for grounding of the pin for Midio128. The old Midio128 does use the display to show status changes and values sent out the Midi interface but not much else. The MIOS STUDIO is the easiest way to read and update the tables for the pins on the DIN & DOUT boards. One problem that I have found with even the V3 software is that the DOUT tables only have 2 saved parameters per pin. The first byte is for the Channel and message event. The second byte is used for the event number. It is my understanding that when the 3rd byte of the Midi message is received that if the values is >63 that the pin will be set ON and if <=63 that the pin is turned OFF. You will have to do your own experimentation to see if this is the case. If you are going to write your own program for the PIC, you will need to know how to use the functions that are supported in the MIOS. If interested, go to http://www.ucapps.de/ then navigate to MIOS->Functions->MIOS8(for PIC) Assembly API. There you will find a large list of all functions and what parameters are passed when the function is called. Pete

Rereading your original post and reading the post from Freddy, maybe I gave you some bad information about twisting the cable. The spec. on page 2 indicates they added pins 15&16 to the connector. They indicated they are not connected to anything on page 8. It would only make sense that they be connected to the back light but when your dealing with China you never know. Maybe you just have to add these wires you talked about to the back of the LCD to get the back light to work. Try looking at the traces on pin 15&16 on the LCD board to see how they are connected to the backlight. May they aren't connected at all.

Pins 15 & 16 are completely isolated from the rest of the 14 pins. If you are sure they are reversed, all you have to do is put a twist into the last 2 wires going to pins 15&16. Remove the connector going to the LCD and separate the last 2 wires from the ribbon cable. Put a half twist on these last 2 wires and re-attach a new 16 pin ribbon connector.

Ah-haaaa, more information is what was needed. As Technobreath states, you MUST have the kick-back diodes on the 2803 connected to your SAM's common rail of +12v. This is pin 10 on the 2803. To check out your ULN2803's, just pull the shift registers out of the sockets of the DOUT board and apply the +12v to the SAM's. With the inputs open, none of them should be turned on. With 12v on, take a volt meter and measure the voltage on pins 1 thru 8 of the 2803. They should all read 0 volts. Now take a wire from +5 volts and touch it to the input of each of the darlington drivers. These are pins 1 thru 8 on the IC. You should see each of the SAM's toggle ON and OFF. Note:Make sure that you have Pins 11 thru 18 going to the SAM magnets. If they aren't, you will blow up your core board by applying 12v to the 5v rail. Another issue might be where you think pin 1 is for the 2803 chip on the DOUT board. Pins 1 thru 8 on the 2803 chip should be going to the shift registers. The 3rd issue is the currents you are pulling thru the DOUT board. You will have to add more ground wires to the already existing DOUT board and tie these to the ground of your hefty 12v power supply ground. Each SAM magnet will pull 500ma thru the 2803 chip. These currents might interfere with the digital signals going to the shift registers if your not careful. Ground loops thru the 10 pin ribbon cable may be another issue. You want to make sure that you only turn ON a max of 4 drivers for no more than 250ms. 80-100ms should be enough to get the SAM to switch states.

A topic was started back in 2008 for this very function so that Stop Action Magnets (SAM's) could be controlled by some of the organ software being developed at that time. The pulse time would have to be at least 80ms long but no longer than 500ms.

Hi John, I am wondering why you are talking about using the ULN2803 chip with the matrix board. It combines the Din and Dout functions which use shift registers 74HC165 and 74HC595. The schematic is shown here. http://www.ucapps.de/mbhp/mbhp_dio_matrix.pdf On the Dout board you can substitute the ULN2803 chips for the resistor packs if you want to drive larger loads. This can not be done on the DIO-MATRIX board. Update: Now that I posted this I wonder if you are talking about another Matrix PCB that I don't know about. Pete

If you are running an unmodified version of Midio128v3, just down load the current release V3.013 which supports 4 Midi ports. Just be sure you also upload the new boot loader at the same time, other wise your USB Midi will not work any more.

Thanks Thorsten, That link worked fine. Just that it was over 15meg that included all of the other projects which I won't be needing in the end. At this time I am just looking at the current code and going to see what I need for my project. I think that the only changes will be in the Midi128_v3 directory but you never know. Will have to take a look in the Makefile and see how the other directories are included in the hex object. Will have to try compiling the unchanged source before adding changes. This could be a month or more. You never know. Thanks again. Pete Knobloch

Hi all, I have a project that I want to build around many of the functions found in Midio128 but can't find the starting HOME path for the files. Every time I think I get to it all the files are .inc files rather than the .c ones. Can anyone help. Pete

On http://www.ucapps.de/mbhp/mbhp_sdcard.pdf the schematic shows DO connecting to DO. But the "NOTE:" says DO connects to SI and DI connects to SO. I found this confusing and by looking at other schematics, found that DO of the core did have to go to the SI of the card. Maybe you have the 2 signals reversed?

It looks like you are right Shuriken. The Mouser picture doesn't match the real board. The board that Jay shows is exactly like the one that I am using on my CORE_LPC17 unit. Does this mean that Mouser is selling the same thing under 2 different part numbers and different costs? 924-EA-XPR-003 & 771-OM13000598

You are right. The pictures may not be accurate. But the real problem might be that the proper board was made by “Embedded Artists†while the one he ordered was manufactured by “NXP Semiconductorsâ€. The real question is are they 100% compatible as far as function and pin layout. The image that is shown for the LPCXPRESSO LPC1769 from Embedded Artists that I bought for my MIDIO128 V3 project matches the image shown in the Mouser web site. BTW-Both boards use the same LPC1769 processor.

If you compare pictures between the right one and the wrong one, the main difference is the pin layout at one end of the board. I tried to find documents on the one you ordered but couldn't find anything to do the pin compare of the pin matrix of the 6x9 pins on the right edge. The good part can be found at http://www.mouser.com/ProductDetail/Embedded-Artists/EA-XPR-003/?qs=S92LKl1JvFyxqKp2Q1rskQ== and it includes a link to a PDF document that has the pin assignments. I don't know if your board will work but just comparing the pictures, the board you have has far fewer parts. And I have found it difficult to find the right part if you just enter “LPC1769†in the mouser search window. Now wonder you ended up with a different board.

Great advise Tim but it seems like you should also include information on how to measure a circuit with power on it. With power applied you almost always want to read voltage across a point, never use the meter on ohms. There may be exceptions but not many. Pete

Just in case someone missed my other post, the MIDIO128 V3.012_pre1 has fixed my Windows 7 and Windows XP issues for file transfers using MSD mode. Thanks Thorsten.

From what I see, your V3.12pre1 has fixed the MSD issue with my PC. I can read and write the files without problems. I am using Windows 7 running on a 64-bit machine. I also tested it on my older Windows XP unit and it also works great. Pete

I reported this very problem a few releases ago. Thorsten responded a 2nd time in post #54 that this is a problem with Windows only and that he was going to add file Xfer to Mios Studio in another release and to ignore this issue for now. I accept this answer but it would still be nice if it worked with my Windows 7 PC. I just tested it on my XP unit and it also fails. Just hoping. BTW-I was having issues with this before the GM5 driver was installed.

I don't need the separate switches either. The shift function works fine for me.

I loaded the midio128_v3_011_pre6 software but only tested it using the Midi player. Its working fine with windows 7 and all 4 USB ports. I went into the .MID panel and noticed for the first time that the encoder knob had more options added to it. Also surprised that the PORT field has completely separate entries for enabling play and record modes for all of the ports like you had discussed in previous posts. Tested playback on all 4 USB ports and Midi Ports 1 & 2 and they work fine. If I enable Midi ports 1, 2, & 3 for both record and playback and then start playing a song, the Midi Port 2 eventually starts sending Program Change 7 messages to ch 2 and repeats this forever. Only way to stop this is POR the board. Suspect issue is due to floating input into the CPU. Funny thing is that the repeated output doesn't happen to Midi port 1. The problem can also be caused by enabling the play & rec for the DI/O port. I tried enabling the MSD mode but had nothing but problems. Even worse issues than before and locked up the PC's USB task and couldn't even shut the PC down normally. But this doesn't seem to be related to the USB 4 port issue does it. Pete