ERROR: EEPROM verify failed on macOS 14.5 and Windows 11

[k6lcm]

Using the current 6.9.10 and 6.9.9 versions, I am getting the following in the terminal when attempting to flash a P8X32A-D40.

Opening file '/Users/levi/Desktop/Pixelmusic/pixelmusic3000e.binary'            
Stepping down to 460800 baud                                                    
Stepping down to 230400 baud                                                    
Stepping down to 115200 baud                                                    
Using single-stage download                                                     
Downloading file to port /dev/cu.usbserial-P97z9aa5                             
12156 bytes sent                                                                
Verifying RAM                                                                   
Programming EEPROM                                                              
Verifying EEPROM                                                                
ERROR: EEPROM verify failed                                                     
ERROR: Download failed

I have tried running proploader.mac from the macOS command line and I am getting the same issue so I am also creating an issue in the parallaxinc/PropLoader project but that appears to be abandoned since 2020.

[Wuerfel21]

That looks like a hardware issue, please detail how everything's hooked up.

[k6lcm]

Thanks for responding. Here is the schematic and board layout I am using. It does seem to send some kind of two-way communication with the board as I see data on both TX and RX pins using a scope. But the project itself is not working and I am, of course, suspicious of the error as the culprit.

[Wuerfel21]

Are you showing all the traces on that board? The Propeller has two power inputs, they both need to be connected, otherwise it won't work right.

[Wuerfel21]

Yeah, the second VDD/VSS pair shows as unconnected in the schematic, too. Fix that first, then try again.

[k6lcm]

Thanks for replying with the suggestion. I checked and there was continuity between those pins already and voltage across them but to be sure, I wired up bodge wires as shown in red. The same issue persists, however. I have quadruple checked the solder joints, too. This is my first propeller project so maybe I have a bad Prop Plug? Not sure. Any other thoughts?

[Wuerfel21]

There's also a pull-up missing on SCL. I think they're both needed.

Does it work when you just load the program to RAM instead of trying to program the EEPROM?

[k6lcm]

The program does not work in RAM either. What value resistor should I stick on pin 6/SCL? 10k to VCC?

[Wuerfel21]

Same as SDA, 10k should be fine.

But if it doesn't run in RAM either, there's some deeper issue, likely bad clock source.

I see there's an LED, can you run a simple blink program?

CON
  _clkmode = rcfast
PUB main
  DIRA[16] := 1
  repeat
    OUTA[16] := 1
    waitcnt(cnt+5_000_000)
    OUTA[16] := 0
    waitcnt(cnt+5_000_000)

If that works (with internal oscillator, which is also used during download), try setting _clkmode = xtal1 (crystal direct) and then _clkmode = xtal1 + pll16x (crystal+PLL)

[Wuerfel21]

• If nothing works, ???
• If RCFAST works but neither XTAL nor XTAL+PLL mode does, check crystal type/connection.
• If XTAL works, but XTAL+PLL doesn't, prop chip somehow got fried, grab another. Either way, make sure to add 0.1µF ceramic capcitors between VSS/VDD on both sides, that's allegedly what stops it from dying like that. It has never happened to me, so idk.

[k6lcm]

Ok, checked the crystal with the scope and I am not seeing anything so that is suspect. I just ordered a few more 5MHz crystals. Will swap those in when they arrive and report back.

[Wuerfel21]

The crytal isn't supposed to do anything before it gets enabled by software. Please do test loading a program with the different clock modes as detailed above.

[k6lcm]

Ah, got it. Your code works (with the addition of setting the frequency using _xinfreq = 5_000_000). The LED is blinking with RCFAST, XTAL and XTAL+PLL. Also, 5MHz clock signal is present on the scope now, as you suspected.

The EEPROM is being written as the program remains persistent after power cycle. So I am at a loss as to why flexprop EEPROM verification is failing and still throwing the message:

Verifying EEPROM                                                                
ERROR: EEPROM verify failed                                                     
ERROR: Download failed 

[Wuerfel21]

To clarify: You can program the EEPROM fine with a small program but it still errors out in the console, large-er program doesn't work. Correct?

[k6lcm]

Actually, flashing the EEPROM with both the larger project and the smaller LED Blink programs all show the "download failed" error.

[Wuerfel21]

Sounds like the beginning of the download works, but then it gets corrupted. Try passing -D loader=rom to proploader.