Finished building, but...

[Milkmansound]

I just finished putting my midibox sid together, with the minimal control unit (6 buttons, encoder, and LCD). I powered it on, and there was no readout on the LCD - also, the regulator on the core module gets super hot. I just finished doube checking everything, including voltages. All seems fine- however, after loading the sysex files there was still no response, and the regulator still gets pretty hot. I am reusing the PS from a 64 - and have been keeping my eye on votlages the entire time. Has anybody had this same misfortune? Is there something obvious that I am missing?  ??? -Tim

[LO]

so the bootstrap is loaded?

and do you get the upload request? before sending the sysex?

[Milkmansound]

no - I get nothing on the display, no request, nothing. I made sure to get one with the standardized pinout as well. What makes me nervous is the regulator getting hot - however, all of the voltages are fine. Should I try using a labratory supply instead of the reused 64 supply? Could the LCD be drawing too much current for the regulator to handle? Or does it always run hot? I may put a sink on it just in case.

The bootstrap was loaded by SmashTV - I ordered my PCB's from him. - Tim

[bosone]

try to connect the midi in/out to midi-OX

the hot voltage regulatror could be due to a wrong pinning of the display ( i had such a problem...)

[pay_c]

Sounds like kinda short or so.

Disconnect everything from the Core (also all the ICs including the PIC). Measure the current, which goes inside the core, it should be faaaaaar below 100 mA.

If it is start to connect one piece after the other (first the PIC, the ICs, e.g. the LCD ... ... ...) and measure the current every time to get the "bad boy".

If it is already a higher current, there´s a short somewhere on the board (can also be some IC upside down or diode or something!).

Greetz

[Milkmansound]

ha! it sounds like I did not get the pinning right on the LCD. The regulator runs cool when the LCD is out of circuit. Here is the new dilemma though - my LCD pin names are a little different than the ones in the schematic - maybe I confused them because of this - here are mine: (btw, this is an HD44780 standard LCD)

1 - A

2 - K (these are the power supply to the lamp)

3 - VSS

4 - VDD

5 - VL

6 - RS

7 - RW

8 - E

9 - 16 - D0-7

they read as follows on the schematic:

1 - B+

2 - B- (power supply)

3 - VS

4- VD

5 - V0

then they appear to be the same after that

Has anyone else run into this before? Bosone - how did you pin yours?

[Milkmansound]

here is some more info -

the core draws about 30ma on its own

when I add the LCD it goes up to about 180ma

when I add the SID (no LCD) it also goes above 100ma

the reg stays cool until either one of these boards is added... what should I expect to draw with them attatched? (btw these tests I did with my labratory supply, not the C64 supply) - T

[TK.]

I'm not sure about the currents, perhaps they are ok (assumed that your LCD has a backlight), but they could be false if your PSU has a max current of 200..300 mA.

However, I think it makes sense to follow all the instructions from the MIDI troubleshooting page:

http://www.ucapps.de/howto_debug_midi.html

There are a lot of tips how to get a sign of life from the core module

Best Regards, Thorsten.

[Milkmansound]

ok, I went through the troubleshooting procedures, and there was no flicker in the midi out LED when I tried that. All other voltages/grounds are ok. Did I fry the optocoupler or PIC by accident? I was working with a wriststrap, but maybe when the regulator overheated it took one or two things out with it. How sensitive are these IC's? Or, maybe you know of something else that I should check? This bums me out :-[ - Tim

[TK.]

Don't panic, it's really hard to destroy the chips!

I hope that the ICs are inserted in the right direction into the sockets?

Another reason could be the crystal: make sure that the two "legs" don't get in contact with the metal case. Check also the connections to the two 33pF caps

Best Regards, Thorsten.

[Milkmansound]

we have flicker! There was a bad solder joint - most likely I accidently wicked it whenI removed some connections from the other modules. I will load Mios, and re attatch the SID module! Thanks for the help - Tim