====== ATGM336H ======
The ATGM336H GNSS module is a Chinese ublox MAX-M8 type clone, suitable even as a drop in replacement. It is based on the AT6558 GNSS SoC.

  * {{ ::at6558_datasheet.pdf | AT6558 Datasheet}}
  * {{ ::atgm336h-5n_datasheet.pdf |ATGM336H-5N Datasheet}}
  * https://makersportal.com/shop/mini-gps-module-atgm336h-antenna
  * https://www.amazon.com/dp/B09LQDG1HY

===== GNSSToolKit =====
  * https://www.icofchina.com/d/file/xiazai/2020-09-22/26ac3f347aca9fc6c3a23db296b0dec0.zip

===== Making Adjustments =====

The ATGM336H can largely be manipulated by sending PCAS commands, the documentation for which are supported is very sparse. Most of these I have captured from the GNSSToolKit application. Without GNSSToolKit, one can echo these commands directly to the device.

^ Description         ^ PCAS             ^ Command                                         ^
| save configuration  | $PCAS00*01       | ''echo -en '$PCAS00*01\r\n' > /dev/ttyUSB0''    |
| hot restart         | $PCAS10,0*1C     | ''echo -en '$PCAS10,0*1C\r\n' > /dev/ttyUSB0''  |
| cold restart        | $PCAS10,2*1E     | ''echo -en '$PCAS10,2*1E\r\n' > /dev/ttyUSB0''  |
| factory reset       | $PCAS10,3*1F     | ''echo -en '$PCAS10,3*1F\r\n' > /dev/ttyUSB0''  |
| stationary mode     | $PCAS11,1*1C     | ''echo -en '$PCAS11,1*1C\r\n' > /dev/ttyUSB0''  |
| GPS Only            | $PCAS04,1*18     | ''echo -en '$PCAS04,1*18\r\n' > /dev/ttyUSB0''  |
| BSD Only            | $PCAS04,2*1B     | ''echo -en '$PCAS04,2*1B\r\n' > /dev/ttyUSB0''  |
| GPS+BDS             | $PCAS04,3*1A     | ''echo -en '$PCAS04,3*1A\r\n' > /dev/ttyUSB0''  |
| GPS+GLONASS         | $PCAS04,5*1C     | ''echo -en '$PCAS04,5*1C\r\n' > /dev/ttyUSB0''  |
| 115200 Baud         | $PCAS01,5*19     | ''echo -en '$PCAS01,5*19\r\n' > /dev/ttyUSB0''  |
| 0.2 Hz              | $PCAS02,5000*2A  | echo -en '$PCAS02,5000*2A\r\n' > /dev/ttyUSB0   |

Some configuration parameters do not have PCAS values and must be sent as raw hex.

^ Description          ^ Command                                                                                     ^
| Enable DOP Messages  | ''echo -en '\xBA\xCE\x04\x00\x06\x01\x01\x01\x01\x00\x05\x01\x07\x01\x0D\x0A' > /dev/ttyUSB0''  |