Trouble Shooting

Trouble shooting can be broken down to generaly one of three catagories:-

1. Problems with the MIDI3c program
2. Problems connecting to a MIDI device with the MIDI3c Interface Unit
3. Problems connecting to a MIDI device without the MIDI3c Interface Unit

Problems with the MIDi3c program

The most common problem is usually due to a shortage of memory. When converting a MID to M3C file or decompressing a M3C for playing, MIDI3c will require additional memory. Although MIDI3c tries to detect a potential memory shortage it is not always possible to accurately determine how much memory is needed. In the normal course of events MIDI3c should terminate the operation in hand and report an error indicating the problem. If, however, MIDI3c does not correctly trap this problem the program may continue on but with the result of generating an incomplete or corrupted file.

Problem: MIDI files will not play
After MIDI3c has started press the <System> icon. If `Memory used' is not displayed at the bottom then press the <DIAMOND> key. To the right of this windows is the amount of Free memory. We recommend a minimum of 200k allowing for all but the largest MIDI files. If you have less than this free then you run the possibility of having insufficient memory should you need to compress/decompress a large MIDI file.

Problem: MIDI files are played but falters
MIDI3c is a very processor intensive program when it is playing a MIDI file. During this time the Psion may not be able to efficiently handle multi-tasking operations and, therefore, any programs running in the background may cause the processor to incorrectly handle the MIDI3c player. It is recommended that all but the most important applications be shut down if you experience faltering when playing a MIDI file.

You should also never switch to another application whilst MIDI3c is playing a tune.

Problems connecting to a MIDI device with the MIDI3c Interface Unit

The most common problem here is that the MIDI Output Port setting is incorrect in MIDI3c Setup. This must be set according to the connection used from the MIDI3c Interface unit to your MIDI device.

For units with the optional RS232 Output Sockets:-

• If you are using the MIDI-OUT connection then you MUST have MIDI Output Port in the MIDI3c Setup Module set to MIDI OUT. Failure to do so will inevitably result in missing notes or no sounds at all. The Port Switch on the MIDI3c Interface Unit should also be set to MIDI.
• If you are using either of the RS232 connections then the Port Switch on the MIDI3c Interface Unit should be set to RS232. You should then also check that the MIDI Ouput Port (in MIDI3c Setup) is set to the RS232 port and correct Baud Rate (check your MIDI device's User Guide for the correct Baud rate setting - this will be either 38,400 or 57,600 Baud).

Problems connecting to a MIDI device without the MIDI3c Interface Unit

The most common problem here is that the cable connections and/or adaptors are wrong or damaged. As various MIDI devices may have different, and sometimes non-standard, connections it is very important that you thoroughly check the connections and adaptors. The PsiWin cable is terminated with a 9-pin plug designed to terminate in to a PC. Most MIDI devices will be supplied with a cable that is also designed to plug in to a PC. We have to, therefore, make the PsiWin cable look like a PC socket. This is achieved with the aid of 2 or 3 adaptors as follows:-

1. A MODEM Adaptor. This device correctly switches the signal lines in the connector to make the PsiWin cable appear, electrically, like a PC socket. This needs to be a TRUE Modem which switches ALL signals in the cable.
2. A GENDER-CHANGER. This is needed to convert the PsiWin socket (which is now terminated with the MODEM ADAPTOR- also a female socket) in to the male socket that the PC has.
3. Optionally, a 9-25 ADAPTOR. The PsiWin cable is terminated in a 9-pin plug. Dependent upon the MODEM ADAPTOR used you will finish up with either a 9-pin connection or a 25-pin connection. Depending on the cable supplied with your MIDI device you may need to convert between either of the two sizes.

Elby Designs can supply a selection of adaptors that meet these various needs. In most instances you will need one of the following two items:-

1. Psion Modem Adaptor. This provides all the functions indicated above in a single small adaptor. The unit has a 9-pin socket for connection to the PsiWin cable and a 25-pin socket for connection to the MIDI device.
2. Elby Modem Adaptor. this provides all the functions indicated above in a short (~10 cm) cable. The unit is terminated with a 9-pin plug at both ends making it suitable for connecting to MIDI devices with a 9-pin PC connector.

If you have supplied your own adaptors then it is important that you have met all the above criteria. The figure below shows the correct wiring for a proper* Modem Adaptor and can be used as a guideline for those wishing to make their own adaptors.

Psion DB9F	MIDI Device DB9/25F
1	NC
2	3
3	2
4	6
5	5
6	4
7	8
8	7
9	NC

You should also check the MIDI Output Port setting in MIDI3c Setup. This will need to be set to either RS232 - 38,400 Baud or RS232 - 57,600 Baud dependent on the MIDI device you are connecting to.

NOTES:

* This article assumes that the MIDI device is providing a standard PC compatible connection in the form of an industry standard DB9 or DB25 connection. MIDI devices using different connectors, for example a Macintosh connector, will need to make the additional conversions as required (contact Elby Designs for guidance).