Hello everyone, been having issues again getting a custom 3.6 board working. Had issues in the past that I was able to get through but now I'm having similar issues that are distinctly different. Old post for context
For context, this is a new iteration of an older board design that I previously had the "teensy 3.6" circuitry working. I was able to program the board and get it operational. This newer board has the exact same schematic with slight PCB routing differences, really shouldn't be causing any issues.
The two cases i'm seeing with this board, when I try resoldering either the bootloader or the crystals is
Case 1 The program pin floats at around 1.2V or so while the reset pin is high. If I pull the program pin low, the reset pin remains high. In this state, without pulling the program pin low, the 3.3V rail on the board is drawing around 24mA.
Case 2 The program pin and reset pins are high, If I ground the program pin, the reset pin gets pulled to ground, (from the previous post, Paul said this was a way to confirm that the bootloader chip is functioning), but then when I release the program pin from ground, it goes high, then very shortly after the reset pin goes back high. I'm guessing some process happens in that short period. Not an expert so not sure what is happening there.
In this case, the power draw on the 3.3V rail is about 18mA, distinctly lower than the other case.
Does anyone have an explanation to what may be going on in these two scenarios?
For context, this is a new iteration of an older board design that I previously had the "teensy 3.6" circuitry working. I was able to program the board and get it operational. This newer board has the exact same schematic with slight PCB routing differences, really shouldn't be causing any issues.
The two cases i'm seeing with this board, when I try resoldering either the bootloader or the crystals is
Case 1 The program pin floats at around 1.2V or so while the reset pin is high. If I pull the program pin low, the reset pin remains high. In this state, without pulling the program pin low, the 3.3V rail on the board is drawing around 24mA.
Case 2 The program pin and reset pins are high, If I ground the program pin, the reset pin gets pulled to ground, (from the previous post, Paul said this was a way to confirm that the bootloader chip is functioning), but then when I release the program pin from ground, it goes high, then very shortly after the reset pin goes back high. I'm guessing some process happens in that short period. Not an expert so not sure what is happening there.
In this case, the power draw on the 3.3V rail is about 18mA, distinctly lower than the other case.
Does anyone have an explanation to what may be going on in these two scenarios?