Davidmarks

I am using a Palm M130 to drive a MIdio 128 board which in turn is driving the solenoids of a street/fairground organ. I gather a number of people are interest in using Palms so if it is of any help here is what i have done. The only suitable software I have been able to find is ITTY Midi. This is a basic midi player which can be downloaded from the states They have a free trial version that you can download free to try which I seem to remember is fuklly functional but limited to a few seconds playing time) The full version was about 17GBP which I thought was pretty good. The ITTY site also sell cables and kits for getting full polyphonic midi out of the Palm - they also have a comprehensive compatibility list which tells you which Palm models you can use ( I bought a cheap black & white one for 4GBP on ebay. It only has 2mb but will operate midi OK.) To get Midi out from the Palm you have to first of all make sure you have a serial cable (or cradle) USB will not do. It is possible to make up a cable which connects the serial D plug to a five pin midi plug. The wiring is simple. There are only two wires and you need to add a 220ohm resistor and a diode which can be buried in the D socket. I can't remember offhand where on the Web I found the details of how to make it but if anyone is stuck I will dig around and try to locate it again. Hope someone finds this helpful. Cheers all

Hi again, Thanks folks, looks as if I was picking up rubbish. I had about a metre of cable from the midio board to the solenoids in the organ and I had mistakenly thought that the internal resistors in the ULN 2308's were sufficient to knock the back emf on the head, evidently not so ! I have now plumbed in loads of IN4001's and the problem (hopefully) seems to have gone away. I will post some info on the main board on Palm and midi and when I have sorted out the technology ( I am pretty ancient) I will send a photograph of the embryo organ

Hi Thorsten, So far I have not been able to determine a precise pattern. I played a lot of ragtime piano midi with no problem but as soon asI tried some "fairground music" I got the sticking problem in a random manner. However, I am using a Palm M130 as the midi player and have a home made lead to convert the serial D plug on the Palm to a midi plug. It is quite a long cable and I also have a couple of long leads supplying the board with 35 volts for the Darlington chips so maybe better screening could be the answer. I will do some tidying up , thanks for the suggestion. Cheers David

Hi, I have a midio 128 with 64 outputs controlling solenoids which are operating pipes on a fairground type organ. Everything OK except one thing. Every now and again a note "sticks" on and i have to shut down and reset. . I have been advised that this is because the system fails to detect a note off signal in the data stream. can anyone help with a possible cure (I can't go off to the beer tent and leave it running in case this happens so it's pretty critical !!)

Hi, Terribly sorry for the long delay in responding, I have not visited the forum recently and have only just seen your post. The organ I am building is a street/fairground organ so the input will be direct from midi files which control the pipes. I have at present a design which uses 120 pipes which comprise 8 bass bourdons 11 accompaniment bourdons, 32 melody double bourdons, 32 melody flutes, 22 counter melody bourdons and 22 counter melody flutes. Sinc I wish to add some percussion, including glockenspiel and some animated figures I am going to need more than 128 outputs. I am proposing to add a second core module and differentiate between outputs by allocating different channels. What I am not sure about is how to connect two core module to the midi player. Can I jus connect the two midi in sockets in parallel ? Any help would be appreciated. When I have this beast working I will be making all the details available for anyone who is interested. Incidentally I have found that many of the models of Palm hand helds which can be bought very cheaply on ebal can be used with the ITTY midi software to cat as a very successful midi player to drive the system

Hi, Once again many thanks Thorsten that's brilliant, exactly what I need. The example you gave was for midi out. I am using midi in to switch solenoids via darlingtons but I presume the same principle applies.i.e. If I want the midi note C5 on channel 3 to operate pin two then the instruction is: 2 = 92 3C

Hi Thorsten. Thanks for that. I have not been able to figure out how in the ini file to set up which channel to use. One other question regarding channels. Is it possible to specify a specific channel for individual notes if so what for example would be the code to enter in the table tthe instruction output to pin 5 midi note 60 on channel 3. Sorry to be a pin.. I am still struggling somewaht (but gradually getting there !) Cheers David

I have after a few false starts constructed a midio 128 board with 64 outputs driving darlingtons. These will operate solenoids to open the organ pallets and admit air the to the pipes. I would like to have the main chromatic scales driven by this board and then construct another to control some "accompaniment" pipes. It would be useful if I could have each of the two core modules operating on different channels. Can anyone tell me if this can be done with the original (16F877) boards as although I would like to try the new system I just can't get my ancient brain around MIOS and I can't even understand if MIOS can do this.You will probably gather that I am clinging on to an understanding of midi by my fingernails ! Any helpful comments would be greatly appreciated.

Thanks for your help folks ! I am now back in action OK. I decided that my system must be clogged up (rather like our road and rail systems here in the UK. So ... I tidied the disc up and I can get to midio 128 again. I bet my neighbours will be pleased to learn that I can now carry on with the construction of my fairground organ:) David

Hi folks. I am experiencing a problem with Thorsten's web site. I can access everything perfectly except the midio 128 page which comes up blank. Thorsten has checked it out and finds that it works OK. I would be very grateful if some of you could check out your access to the midio 128 page - any other suggestions would be welcome. Thanks David

Having decided to build a Midi controlled street/fairground organ I studied Thorsten’s fantastic web page with great interest. After much deliberation as to whether or not my ancient brain was up to building and running Midio 128 I took the plunge. Ordered the pcb’s from Mike (brilliant service) soldered them up, programmed the PIC, fired it all up, fed it with Cubase and to my amazed delight it seems to be working OK. Now comes the problem… I have 64 LED’s connected up to two output X4 modules and they are responding to notes from C2 upwards. But how do I get the notes below C2 ? I suspect it has something to do with the ini file but I can’t find an ini file. I notice in the source code which Thorsten kindly sent me that there is a file called presets which contains some likely looking tables ! Forgive the dumb questions (my brain, like the rest of me is ancient!) but any pointers as to the general direction I should be heading (other than the window ledge of a tall building) would be appreciated. But thanks again to Thorsten for a brilliant web site. David Marks