mDot UART (RX) issues on DK and micro DK
- This topic has 2 replies, 2 voices, and was last updated 5 years, 11 months ago by
.
-
G’day all,
I am having issues connecting two different GPS modules’ (UART) output to a mDot:
Originally, I tried using the DK:
Connecting a RPi3 to it works, as does a “Silicon Labs CP210x USB to UART Bridge”, but a Mikroelektronika “GNSS 5 Click” or Quectel “L80-R” does not “show up”.
I measured a dramatic drop in p-p voltage swing (from 3V3 to about 0V33) when connecting the GPSs’ UART_TX to the UART_RX pin (Arduino D0) of the DK (incorrectly labelled D1 on the available schematic).The GPSs UART outputs work correctly when driving a Pi or the UART Bridge.
Also, the GPSs UART outputs work correctly if the mDot is removed from the DKs and powered externally!I cannot see any issues with the schematics causing this. As far as I can tell, the uDK doesn’t modify the signal at all (no resistors (apart from 0 Ohm) and no caps!).
The DK is labelled “MTUDK2-ST, B/O:MDOT, P/N:MTUDK2-ST-MDOT, SKU# 94558010LF, DOM: 2016.11.17, Serial:(S)18994413” and
the uDK is labelled “Model: MTMDK-ST-MDOT, SKU #: 94558020LF, Serial#:19544825, DOM:201801.15”.As I hope you can see, I have proven that every component works well when connected to “something else”, but has issues when using either of the DKs. I, also, hope you can see this is not a Baud rate (or any other setting) issue!
I have looked hard, but have not found any reference to the problem I am experiencing.
Any ideas, please?
- You must be logged in to reply to this topic.