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new_ · 10-20-2019, 06:04 PM

Thanks to everyone contributing to this thread, it's been very useful getting me this far.

I've followed the instructions for my PW2 (firmware 5.9.4).

I've got my serial to USB adapter connected to ground, TX and RX on the PW2 via some pins.

I'm getting the full boot output in PuTTY (using Windows 10), but I can't interrupt the boot.

Here's what I've tried:

I have held multiple buttons down whilst the PW2 boots, many times, so I'm confident it's not the timing.
I've jumped the TX and RX pins right next to the PW2 board, and pressed keys on the keyboard, I can see the key strokes in PuTTY.
I've gone through the log from PuTTY and there are no key strokes in it (unless I jump the pins manually, then I can see the key strokes in the log).
I tried soldering to the RX pad, it went OK, I've now got a wire on that pad, rather than a pin, but it didn't help.
I tried using the alternative pads on the other side of the PW2 board. That didn't help either.
Tested the adapter with a Raspberry Pi 2 to confirm that it's sending and receiving, it worked as expected.

As the boot output is getting to PuTTY from the PW2, and the key strokes are coming through when I jump the pins right next to the PW2 board, I think the issue is with the RX on the PW2.

This is the serial adapter I'm using:
DSD TECH USB to TTL Serial adapter with FTDI FT232RL Chip Compatible with Windows 10, 8, 7 and Mac OS X

The instruction slip that came with it does mention in one place that the level can be set to 1.8V, but I don't think it can (other places say it's 3.3V or 5V only).
I've been using it with 3.3V output.
I've read this thread, and at least a couple of people report that 3.3V has worked on their hardware, but I understand that 3.3V is risky, and 1.8V is recommended.

Given that I can see the key strokes in PuTTY when my TX and RX pins are jumped right next to the PW2 board - could the fact that I'm using 3.3V be preventing the signal getting to the PW2 somehow?

Is there any way to test whether the issue lies with the serial adapter or the PW2 RX pad without buying a new adapter?

Thanks in advance for any answers or suggestions.

10-20-2019, 06:04 PM	#452
new_ Junior Member Posts: 1 Karma: 10 Join Date: Oct 2019 Device: PW2	Thanks to everyone contributing to this thread, it's been very useful getting me this far. I've followed the instructions for my PW2 (firmware 5.9.4). I've got my serial to USB adapter connected to ground, TX and RX on the PW2 via some pins. I'm getting the full boot output in PuTTY (using Windows 10), but I can't interrupt the boot. Here's what I've tried: I have held multiple buttons down whilst the PW2 boots, many times, so I'm confident it's not the timing. I've jumped the TX and RX pins right next to the PW2 board, and pressed keys on the keyboard, I can see the key strokes in PuTTY. I've gone through the log from PuTTY and there are no key strokes in it (unless I jump the pins manually, then I can see the key strokes in the log). I tried soldering to the RX pad, it went OK, I've now got a wire on that pad, rather than a pin, but it didn't help. I tried using the alternative pads on the other side of the PW2 board. That didn't help either. Tested the adapter with a Raspberry Pi 2 to confirm that it's sending and receiving, it worked as expected. As the boot output is getting to PuTTY from the PW2, and the key strokes are coming through when I jump the pins right next to the PW2 board, I think the issue is with the RX on the PW2. This is the serial adapter I'm using: DSD TECH USB to TTL Serial adapter with FTDI FT232RL Chip Compatible with Windows 10, 8, 7 and Mac OS X The instruction slip that came with it does mention in one place that the level can be set to 1.8V, but I don't think it can (other places say it's 3.3V or 5V only). I've been using it with 3.3V output. I've read this thread, and at least a couple of people report that 3.3V has worked on their hardware, but I understand that 3.3V is risky, and 1.8V is recommended. Given that I can see the key strokes in PuTTY when my TX and RX pins are jumped right next to the PW2 board - could the fact that I'm using 3.3V be preventing the signal getting to the PW2 somehow? Is there any way to test whether the issue lies with the serial adapter or the PW2 RX pad without buying a new adapter? Thanks in advance for any answers or suggestions.