I have a project where I need a Arduino Mega 2560 to act as a serial data controller. Here's my issue, it needs to send command strings of bytes in the manufactures format BINR. The device will then send back a stream of bytes formatted (10 startbyte, message type byte, data, 10 03 end byte combo). As an example however if I request GPS empheritis I will have at the least 12 messages 84 bytes long. I then need to pull most of the bytes out and reformat for transmission in RTCM SC10403.1 format. I believe I can get the code written to put these into arrays however I am thinking I will be out of SRAM right away. Does that sound right?
If so how can I add external RAM to the device to use for my array storage. Also is there a limitation to the addressing size the ATMEGA can use?