<![CDATA[GPS AT6558 Core Gray Confusion]]>Hi all, this is my first post here as I haven't been able to find this info anywhere else. I recently purchase a Core2 Gray for use with a GPS/IMU project. I also purchased the AT6558 GPS unit because it appeared to just plug right in(or so I thought).

Documentation on the GPS shows a pinmap with GROVE C on the M5Core which is RX(16), TX(17), 5V and GND. It has that lining up with TX,RX,5v, GND on the GPS. https://docs.m5stack.com/#/en/unit/gps

So my GROVE port is red so A? The documentation when I bought this said "You can plug it into the Grove port C on an M5 Core. I guess I am/was confused as to whether or not this should work. Specs on the M5Core Gray list the "Port" as TypeC which says I2C+I/O+UART. I think the Type C threw me off as it was somehow configurable

So can someone clear up this confusion for me as to what M5PORT EXPLAIN is on the site showing

  • Port-A(Red) G21/22 I2C

  • Port-B(Black) G26/36 DAC/ADC

  • Port-C(Blue) G16/17 UART

So out of all that :)

  1. Am I correct to assume that my Core Grey GROOVE connector is fixed I2C?
  2. Can I communicate with the GPS unit via I2C? I know there are some gps modules with special firmware that makes it possible but don't know about this GPS module. I was thinking maybe i just missed a setting.

I am thinking at this point my only option to use this GPS Unit is to hook it up to 16/17 UART on the M5 or go back to one of my UBLOX modules.

Thanks in advance!
Matt

]]>https://community.m5stack.com/topic/3212/gps-at6558-core-gray-confusionRSS for NodeThu, 30 Apr 2026 01:32:26 GMTWed, 21 Apr 2021 19:27:27 GMT60<![CDATA[Reply to GPS AT6558 Core Gray Confusion on Thu, 29 Apr 2021 22:45:28 GMT]]>I mistaking posted this in core2, but wanted to chime back in as I have it working. Still not sure how to get the right port with my gray but if someone finds this I wanted to link the solution.

https://127.0.0.1:6060/topic/3217/hardwareserial-ss-2-uart-connection-on-16-17-for-a-gps-antenna

]]>https://community.m5stack.com/post/13670https://community.m5stack.com/post/13670Thu, 29 Apr 2021 22:45:28 GMT<![CDATA[Reply to GPS AT6558 Core Gray Confusion on Thu, 22 Apr 2021 13:24:19 GMT]]>Thanks for the reply ajb2k3!

The gray i have is standard, no additional base/modules. It had everything i needed except GPS which is why I got the Unit before noticing the GROOVE connector wasn't UART. 16/17 are clearly marked on the base I was just hoping for a clean/durable connection between the GPS Unit and the Core that the dupont connectors wouldn't provide.

Ill give the unit a test jumpering it to 16/17/5v/gnd on the dupont connectors.

]]>https://community.m5stack.com/post/13592https://community.m5stack.com/post/13592Thu, 22 Apr 2021 13:24:19 GMT<![CDATA[Reply to GPS AT6558 Core Gray Confusion on Thu, 22 Apr 2021 05:11:21 GMT]]>The Red grove port is for I2C but can be used for some other uses.
The GPS modules uses UART, the pins for this can be found on the mini bus
What base do you have connected to the gray as the UART pins tx/rx are marked on the base with male and female dupont connectors.

]]>https://community.m5stack.com/post/13588https://community.m5stack.com/post/13588Thu, 22 Apr 2021 05:11:21 GMT