Notes on serial data formats:

EM1000 and EM3000:
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This is a 10 byte message:

Byte 0: Status byte in the range of 0x90 to 0xA0 for EM3000.  0 for EM1000
Byte 1: Header byte (always 0x90)
Byte 2-3:Roll in 0.01 degree units (positive roll is port side up)
Byte 4-5:Pitch in 0.01 degree units (postive pitch is bow up)
Byte 6-7:Heave in 1 cm units (postitive above datum per TSS manual)
Byte 8-9:Heading in 0.01 degree units (0 to 359.99)