defragster
Senior Member+
220-330 is close enough - since they aren't marked I only assumed they were resistors - and measuring takes disassembly.
And yes - it is noted above the resistors are NOT on the Beta 2 breakout - that is why T4-2 is failing for me using a single T_3.1 for debug terminal - the UART standby voltage prevents the T4 from starting up.
I wire wrapped a 330 Ohm and a 200 from the Breakout Active posts to the pair of unconnected posts toward the GND post. This give a working 2 MB/sec Serial1 to the T_3.1 - if T_3.1 is OFF when the T4 is powered or 'switched On'
With the 330 inline I can power on the T4-2 with Tx to the T_3.1 Rx and get output and it gets to setup() and runs, without that it will not make it to setup().
That puts the 200 on the T4-2 Rx from the T_3.1 Tx and even alone that will not let the T4-2 get to setup.
Like my earlier noted and logged T4-1 issue - when connected to T_3.1 they have to be powered down before T4 will go through startup into setup().
Paul: I assume I'm explaining this properly and correct in seeing it as a significant issue with a relatively accurate analysis?
I'm out of my element here with details - but using a Teensy with EchoBoth for UART to SerMon for debug does not allow T4-2 to cold start.
<edit> A single wire Serial4 Tx to T_3.1 Rx for boot debug at 115200 does work - unless I also connect Rx from T_3.1.
> But after it is running Power Off works, but Power On will not restart - though the Green LED does light up Full bright and nothing comes out the debug port Serial4 in that case.
This might explain the odd behavior that stopped me from going further on T4-1 debug code.
Also when it functions on cold start with power switched by USB device it will at times work, when it will not work to Power On after it was powered Off with Breakout Button when the T_3.1 was connected.
Also I do have a USB TTL adapter and only seems to supply 9 mA on Tx when idle - that seems to allow Cold start, but not Button power On.
@mjs513 - when you were having your Faults while working - what was your UART/Debug setup?
@KurtE - I wonder how much/little current is coming from your TTL/USB Adafruit CP2104 or other units in use.
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