Hi...
Just to help users here on the ATGM336 GPS...
I tried to configure the popular (e.g. cheap) ATGM336 GNSS/GPS receiver, but most information is in Mandarin...
Finally, after online translation and experimentation, i've created this info that might help anyone here.
Main issue with ATGM336 is too heavy load (all NMEA sentences enabled / GPS and Beidou enabled) for the default 9600 bps baudrate, so some configuration is requied...
Hope some users will find these informations useful...
===============================================================
; ATGM336H (AT6558 Silicon) configuration:
; 9600,8,n,1
; Checksums, like NMEA sentence checksums,
; are simple XOR's between '$' and '',
; excluding both '$' and '' .
;===========================================
; = 0x0D, 0x0A required after each
; sentence. Not computed in checksum.
$PCAS00*01 ; Save config to flash
;-------------- BAUD RATE -------------
$PCAS01,0*1C <CRLF> ; --> 4800 bps
$PCAS01,1*1D <CRLF> ; --> 9600 bps
$PCAS01,2*1E <CRLF> ; --> 19200 bps
$PCAS01,3*1F <CRLF> ; --> 38400 bps
$PCAS01,4*18 <CRLF> ; --> 57600 bps
$PCAS01,5*19 <CRLF> ; --> 115200 bps
;---- FIX RATE (in milliseconds) -----
$PCAS02,1000*2E <CRLF> ; 1000 ms fixes
$PCAS02,500*1A <CRLF> ; 500 ms fixes
$PCAS02,200*1D <CRLF> ; 200 ms fixes
$PCAS02,100*1E <CRLF> ; 100 ms fixes
; ------- outputted sentences --------
; Checksums:
; Odd number of "ones": 03
; Even number of "ones": 02
$PCAS03,1,0,0,0,1,1,0,0*03 <CRLF>
$PCAS03,1,1,1,1,1,1,0,0*02 <CRLF>
; | | | | | | | |
; '-|-|-|-|-|-|-|--> GGA
; '-|-|-|-|-|-|--> GLL
; '-|-|-|-|-|--> GSA
; '-|-|-|-|--> GSV
; '-|-|-|--> RMC
; '-|-|--> VTG
; '-|--> ZDA
; '--> TXT
```
;
; Examples:
;
; RMC only:
$PCAS03,0,0,0,0,1,0,0,0*03 <CRLF>
;
; GLL and VTG:
$PCAS03,0,1,0,0,0,1,0,0*02 <CRLF>
;
; GSA, GSV and RMC:
$PCAS03,0,0,1,1,1,0,0,0*03 <CRLF>
;
;----------- CONSTELLATIONS -----------
; bits: 1 = BDS; 0 = GPS
$PCAS04,3*1A <CRLF> ; BDS + GPS
$PCAS04,2*1B <CRLF> ; BDS only
$PCAS04,1*18 <CRLF> ; GPS only
; Apparently, some AT6558's can
; decode GLONASS, but not mine.
;======== UNTESTED SENTENCES ============
;----- NMEA protocol type selection -----
$PCAS05,1*19 <CRLF>
;----- Query module information -----
$PCAS06,1*1A <CRLF>
;----- Set to restart -----
; The module can be self-restarted as needed in an abnormal state, without having to be powered off and restarted all the time.
$PCAS10,0*1C <CRLF>
;sm
; 0 = Hot start. No initialisation information is used and all data in the backup storage is used.
; 1 = Warm start. Do Not use the initialisation information, clear the ephemeris.
; 2 = Cold start. Do Not use the initialisation information and clear all Data except the configuration in the backup storage.
; 3 = Clear all data in the memory and reset the receiver to its factory default configuration.
; sm = Startup Mode
;----- Set low power mode -----
; You can enter the low-power mode by pulling down the ON_OFF pin. Some slots do not support low-power instructions for the time being.
$PCAS12,0*1C <CRLF>
;----- Configure whether to receive any satellite in the system -----
$PCAS15,2,FFFFFFFF*37 turns-on Beidou's satellites 1-32
$PCAS15,2,FFFFFFE0*42 turns-on Beidou's satellites 6-32, Beidou's satellites 1- 5 is turned off
$PCAS15,4,FFFF*31 turns-on SBAS satellites 1-16, that is PRN=120-135
$PCAS15,5,1F*47 turns-on QZSS satellites 1- 5, namely PRN=193, 194, 195, 199, 197
;
; 2=Beidou Satellite 1-32
; 3=Beidou Satellite 33-54
; 4= SBAS Satellite 1-19
; 5= QZSS Satellite 1- 5