Access serial console with USB-TTL adapter or equivalent

Help with Raspberry Pi Foundation Boards (Raspberry Pi, Pi Zero, Pi Zero W, Pi A, Pi B, Pi B+, Pi2 B, Pi3 B, Pi 3 B+)
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vk3fjc
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Location: Melbourne, Australia

Access serial console with USB-TTL adapter or equivalent

Post by vk3fjc »

Hi all,
I would like to be able to access my zumSPOT's serial console using a UART TTL terminal (USB to TTL adapter or other UART TTL device like amicro controller) but so far I had no success.
Does anyone know what needs to be "hacked" in Pi-Star to do this unless it's already built-in and I missed something?
Thanks for your help.

73s de Guillaume VK3FJC/F4FJC
Guillaume (VK3FJC / F4FJC)
vk3fjc
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Location: Melbourne, Australia

Re: Access serial console with USB-TTL adapter or equivalent

Post by vk3fjc »

Hi,
Thank you for your reply. Unfortunately I now realize I didn't explain the situation correctly.
I do not want to access the zumspot modem via serial, flashing works very well with Pi-Star without doing this.
What I want is to access the Pi-zero-W tty console via uart while the zumSPOT is connected.
Is this possible or does the zumspot modem (or other board) use the Pi uart for communication (I thought it was using GPIO)?
Thanks,

Guillaume
Guillaume (VK3FJC / F4FJC)
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Re: Access serial console with USB-TTL adapter or equivalent

Post by AF6VN »

vk3fjc wrote: Thu Aug 23, 2018 11:29 am Is this possible or does the zumspot modem (or other board) use the Pi uart for communication (I thought it was using GPIO)?
I couldn't find any on-line schematics or manuals for the device, but the other respondent's last sentence seems to imply you can't... (emphasis mine)
ct1dvm wrote: Thu Aug 23, 2018 6:13 am Re-enable the Pi boot config tty console if you want to play with the pi via uart with zumspot removed.
Looking at my DV-Mega/R-Pi3 (my understanding is that most of these boards are similar) the DV-Mega connects to the first 10 pins (5 rows). Those are

3.3V 5V
SDA 5V
SCL ground
GPCLK0 TxD
ground RxD

I'd suspect the software has pin-muxed those into plain GPIO.

--
AF6VN
Dennis L Bieber
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MW0MWZ
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Re: Access serial console with USB-TTL adapter or equivalent

Post by MW0MWZ »

The ZumSpot modem is connected to the UART, so there is no hardware serial console available, this has to be turned off to enable the use of the hats.
Andy

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Re: Access serial console with USB-TTL adapter or equivalent

Post by MW0MWZ »

Humm, I should have added here, that you can of course, add a USB UART, and then spring a terminal via Getty on the USB UART, but what's the point?
Andy

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