Build debugging
#11
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(11-01-2021, 11:31 PM)admin Wrote: Check to make sure that your solder joints are good at the 8 pin video connector, as well as the VIC-II chip.

The 74LS629, MC4044, and 74LS74 along with the crystal (and of course VIC-II) are responsible for the video output.  Check all of these to make sure that they are inserted in the proper direction... in fact, check all of the chips to make sure that all of the notched at facing towards the rear of the board.

Making incremental progress... I have a flashing dead test screen now... Albeit with all ROMs and both CIAs removed.

I had been trying to work with a GAL PLA and then a PLAnkton, but wasn't having luck with either. 
Then I realized that the BOM wanted a 82S100, rather than a 906114-01, so I managed to dig up a working one.

Next, I took a look at the joints on the 8-Pin circular DIN connector, which all appeared to be fine, but then I realized something that I wasn't expecting. 
The angles on the upper-most pins appeared to be off. To verify this I tried another video cable and sure enough it didn't fit properly.
It turns out that the pins were organized in more of a "O" shape than an "U", so I wound up replacing the connector with one that fit my cables better.

   

I was finally able to see video activity in the form of a power on flicker (whew hoo!), but the screen was still black (uhg!).

I removed all of the ROMs and both CIAs, and on the next boot, Dead test finally started to give off some flash codes.

Now, I just need to retest all of my chips... I'll need another time window to get into all that.

Thank again for the suggestions.
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#12
The difference between the connectors is that the original version is a 262 degree, and the other one you have is 270 degree. I have both types, but the 262 degree version is what is included in my kits (or should be!)

I have used EVERY type of PLA and replacement known.. I think 13 different ones now, and they all work.
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#13
(11-05-2021, 05:42 AM)admin Wrote: The difference between the connectors is that the original version is a 262 degree, and the other one you have is 270 degree.  I have both types, but the 262 degree version is what is included in my kits (or should be!)

I have used EVERY type of PLA and replacement known.. I think 13 different ones now, and they all work.

Took a break from this build for a while, so checking back in with some updates....
I systematically stepped through and checked every chip again with a Backbit tester, which confirmed that they're all working.
One notable exception is the 74LS629, which the tester doesn't appear to detect properly, but I tried multiple chips and none of them made a difference. I also left a note on Evie's forums regarding this test.

Just to be safe, I'm using a known good (and relentlessly tested) 82S100 PLA, which should rule that out as a probable cause.

I've also tried several types of video cables, but I still haven't gotten the system to reliably boot with the dead test cart, even with all ROMs, CIAs and the SID removed.

I quintuple-checked and reflowed my solder joints, which all appear to be good, so I'm back to feeling at a loss.

Really want to get this system working, so I'm open to all reasonable suggestions...
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#14
For any cartridges that use the $E000 address you need to make sure that the reset type is set to not use Exrom. This was not the default for the first few dozen boards that I shipped out. You can check and change this through the OLED screen and menu. The real dead test cartridge uses $E000.
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#15
(11-27-2021, 10:40 AM)admin Wrote: For any cartridges that use the $E000 address you need to make sure that the reset type is set to not use Exrom.  This was not the default for the first few dozen boards that I shipped out.  You can check and change this through the OLED screen and menu.  The real dead test cartridge uses $E000.

The v1.2 manual doesn't appear to have a lot of info regarding the wiring and connecting of the OLED.
Is there a separate doc for that?

Thanks again!

UPDATE:
I took a quick look at the add-ons & accessories for the ICS64 and realized that there's enough info there for me to work with...
(e.g., It's an I2C display, as opposed to an SPI, it uses a custom pin-out of VCC/GND/SCL/SCA, etc.) 

   
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#16
The ICS64S board is marked with the pinout for the I2C OLED screen as + - 1 2, where + and - are +5v and Ground, 1 is SCL and 2 is SDA.
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#17
So, I just ran into the exact same problem that you described early on. Powering on my ICS64S board doesn't even "flash" the monitor. Nothing happens at all. I pulled the monitor cable from the ICS64S board while the power was on and I had a IEC connector touch the board at the same time (I have the ICS64S board sitting by itself with no case). Normally this is not a problem, but in this case it shorted out the video port, which has power on it. That caused the fuse to blow. Once I replaced the fuse, I got the typical "flash" the instant power is turn on, and then normal video. Check your fuse. Smile
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#18
(11-27-2021, 10:40 AM)admin Wrote: For any cartridges that use the $E000 address you need to make sure that the reset type is set to not use Exrom.  This was not the default for the first few dozen boards that I shipped out.  You can check and change this through the OLED screen and menu.  The real dead test cartridge uses $E000.

Some more updates...

I bought the correct type of I2C OLED and started messing with the board config. 
As you pointed out, once I disabled the EXROM under "Reset Method", my Dead Test cart started working reliably, with every reboot.
Now, I'm getting a single flash, which is difficult to diagnose because all of my DRAM chips are testing properly...

So, some progress made, but more work ahead...
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#19
Glad you got the dead test working!
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