I bought a MT3329 GPS in 11/08/2010 and later another one in 1/26/2011. For my surprise the binnary protocal is different. The first one starts with a header 0XB5,0X62, 0x01, 0X05. The latest one the preamble header ix 0XD0, 0XDD and a Payload byte that I di not understand very well. The order of the data bytes is also different. I already did some small programs using the first protocol, so, I wanted keep the same. Can I change the firmware version to go back to the same protocol?
I think the I read some were that we could program the type of the protocal at the sartup. Lets say that I want binnary @115200 baudrate. Can you please confirm if it is possible to do this? This way we only need one RX channel to read the GPS and a TX channel to send the decoded data to other system insted of have two UARTS one to set up the protocol (binnary and the baud rate) and the TX of other UART to send the decoded data to other system.
Can you please help and clarify my doubts and help to change the protocol?
Thanks in advance.
Follow this link for the firmware update. Not sure if there is a link for firmware downgrade though....
These are the commands I know that are used in the AP/AC code:
I'm sure you can find more on the internet... :)
Tthanks for your reply and information. What I would like to know if it is possible change for binary protocol and lets say 115200 Baud rate and this be logged in the firmware, to avoid avery time I power up I have to change the parameters.
Your reply or some one else is appreciated.
Thanks in advance,
At least some of the MTK GPS chipsets should be able to change the default start up baud rate. Look at the PMTK390 command. I'm not sure about binary vs. NMEA mode.
One reference for the command is:
I haven't tried this command. I just remember it because some older OSDs needed a certain initial baud rate to work correctly and this was suggested.
Not sure how exacltly it works, but have a look at this zip. It has an utility to configure and test the GPS.
Since the MTK has a custom firmware for diydrones, I'm not totally sure it will work but worth a try.
John and Emile,
Thanks for your reply.
It was good if I could change the default baud reate, it would save me a UART Port. For my project I only need a RX from the GPS and a TX to transmite data to another system,
I am going to give a try to your sugestions.
Thanks again for your reply and help.