dtg84

SammichSID trouble ::SOLVED::

12 posts in this topic

UPDATE: I stupidly supplied the LCD with more current than it needed. Which was odd, because when I first tested it with the shunt placed in 5V, it was completely dark, even after adjusting the trimpots. Maybe the incorrect IC i placed on the Control surface earlier drew more current from the LCD?

UPDATE: Thought it was solved, but something emitted smoke! I am not sure where it came from, as the control surface was plugged in at the time. I verified that this does not occur with the control surface plugged in.

UPDATE: Below is SOLVED

Tried to test sammichSID today, although I can't get it to work. Passed all the voltage tests, made sure to test between pin 14 and pin 28 on the SID IC sockets (pin 28 reads 8.97 V on my DMM, pin 14 read 0 V). However after I powered it on, I quickly realized I forgot to put in the capacitors for C1/2L, C1/2R!! Do you think I toasted my SIDs?? In any event I put the capacitors in and then tried to test it...

Setup with MIOS was successful. i was able to upload PIC firmware and install sammichSID .hex file just fine. However, when testing audio of the sids it is extremely quiet and noisy. It also seems to drone on one pitch, and sending midi data only seems to effect it momentarily before it goes back to the initial pitch...

Any ideas?

Edited by dtg84

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All is solved, and all is well in SammichLand!!!

Edited by dtg84

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Hi,

you mention channel 3/4, are you aware that the audio out is a stereo jack? The other jack is the audio input.

The audio out is the jack closest to the power in.

Apart from that, check that you have all of the ICs inserted the right way round, check the midi and voltage jumpers too.

It could be that the noise is just the SIDs normal noise and you are getting no midi to the core.

I have tried my sammich with a pair of working but very noisy 6581s and it sounds quite similar. I don't like the noise so I have gone back to the 8580s and all is good.

Good luck.

Tim.

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you mention channel 3/4, are you aware that the audio out is a stereo jack? The other jack is the audio input.

The audio out is the jack closest to the power in.

Oops. I guess that is what I get for using sammichFM's rear panel as a reference. Thanks.

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Apart from that, check that you have all of the ICs inserted the right way round, check the midi and voltage jumpers too.

It could be that the noise is just the SIDs normal noise and you are getting no midi to the core.

I have tried my sammich with a pair of working but very noisy 6581s and it sounds quite similar. I don't like the noise so I have gone back to the 8580s and all is good.

Checked all ICs to see if mounted correctly. Checked midi and voltage jumpers (JP is horizontal since I am using 8580s). I am not sure... maybe these SIDs are no good? I haven't tested them personally, but I bought them from a reputable seller on these boards who tested them. I have checked my solder with the loupe and they all look good.

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Sorry it has been a long day, of course the midi is reaching the core, else no upload of the sammich hex would have occurred.

F1 on the control surface should make the sammich play the currently selected patch, the 1*** is highlighted on the LCD when playing.

Does this do anything?

If all of the voltages etc. are correct then it looks like the sids could be at fault.

The only other thing I can think of is possibly you have mixed up the 74hc168s and 74hc595s, I did it but spotted the error before I applied power, as they are the same size.

Tim

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F1 on the control surface should make the sammich play the currently selected patch, the 1*** is highlighted on the LCD when playing.

Does this do anything?

No, although panel doesn't appear to be working correctly either. Argh!

If all of the voltages etc. are correct then it looks like the sids could be at fault.

There goes 50 euros down the proverbial drain...

The only other thing I can think of is possibly you have mixed up the 74hc168s and 74hc595s, I did it but spotted the error before I applied power, as they are the same size.

Are you referring to the voltage regulators? I made this mistake too, but caught it before I supplied power to the SIDs.

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The 74hc165s (sorry typo in my last reply) and 74hc595s are the 16pin dil chips.

If the control surface is not working then you may have mixed them up.

74HC595s are for the DOUT part and run the LEDs (IC3 and IC4 on the control surface) and the SIDs (IC2L and IC3L on the main board for the SIDs), the 165s (IC1 and IC2 on the control surface) are the DIN part and are for the control surface.

Chances are that the SIDs are ok, they are just not being told what to do if these chips are in the wrong sockets.

Edited by gomiboy99

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The 74hc165s (sorry typo in my last reply) and 74hc595s are the 16pin dil chips.

If the control surface is not working then you may have mixed them up.

74HC595s are for the DOUT part and run the LEDs (IC3 and IC4 on the control surface) and the SIDs (IC2L and IC3L on the main board for the SIDs), the 165s (IC1 and IC2 on the control surface) are the DIN part and are for the control surface.

Chances are that the SIDs are ok, they are just not being told what to do if these chips are in the wrong sockets.

HAHA!! You were right, the two ICs in question were swapped. I replaced them and now it works beautifully!!

Thanks!!

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UPDATE: Thought it was solved, but something emitted smoke! I am not sure where it came from, as the control surface was plugged in at the time. I verified that this does not occur with the control surface plugged in.

I discovered (the hard way) that this is the low-powered LCD. Which is odd, because when I first tested it with the 5V, the screen was completely dark, even after adjusting on the trim pots. Only after I put in the 12v jumper did it start to be visible. I guess after I swapped the ICs into their right spots, the current readjusted itself somehow (i don't know much about electronics, as you can probably tell). It seems to work now (but for how long...)

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At least one problem is solved.

I guess the smoke came from the LCD, I think the default negative green display is 5Volt only but it needs a link placed on the main board to short the resistor for the high power display. There is something in the build guide that mentions this.

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At least one problem is solved.

I guess the smoke came from the LCD, I think the default negative green display is 5Volt only but it needs a link placed on the main board to short the resistor for the high power display. There is something in the build guide that mentions this.

Yes you are right, this was in the build guide. I initially tested it with a shunt in 5V and without the shunt in the JR4 header (i think that was the one that supplied 250mA of current)and it seemed that the LCD wasn't getting any power at all. So I tried the 12V and it started working... until last night when it started emitting a nasty smoke. I am surprised that it still works (no telling for how long though). Now my room smells like chemicals...

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