Hi,
I purchased 2pcs. of MTK 3339 based GPS (GTOP PA6H) modules, they are very similar as regarding the footprint with the previous MTK3329 based units (GTOP PA6B) so I could fit one of them on a custom made PCB. The problem is that I could not find any custom firmware (for MTK3339) for proper working with APM 2.x… I mean something similar with (https://code.google.com/p/ardupilot-mega/downloads/detail?name=AXN1.51_2776_3329_384.1151100.5_v19.bin&can=2&q=)]this custom firmware (AXN1.51_2776_3329_384.1151100.5_v19.bin) for MTK 3329 chipsets (this one changes the default baud rate to 38400 and the refresh rate to 5Hz).
My question is, does Arduplane sets these 2 parameters (baudrate and refresh rate) for the GPS unit at start-up (38400 and 5 Hz)? The stock MTK 3339 firmware defaults are 1 Hz and 9600 baud rate and it accepts commands for it but these settings are stored in the volatile memory so they won’t last without permanent power.