User`s guide

Chapter 5 - I/O Commands
DATUM SELECT COMMAND (@@Ao)
Motorola Binary Format
Query currently used Datum ID:
@@AoxC<CR><LF>
where:
x =1 out of range byte: 0xFF
Checksum = 0xD1
Message length: 8 bytes
Complete hex string to query current Datum ID:
0x40 40 41 6F FF D1 0D 0A
Change currently used Datum ID:
@@AodC<CR><LF>
where:
d = datum ID 49 or 50 (0x31 or 0x32)
C = checksum
Message length: 8 bytes
Response to either command:
@@AodsssffiiffffxxyyzzC<CR><LF>
where:
d = current datum ID: 49 or 50 (0x31 or 0x32)
sssff = semi-major axis (m)
where: sss = integer part 6,000,000..7,000,000
(0x56 0x8D 0x80 .. 0x6A 0xCF 0xC0)
ff = fractional part 0..999 (0.0..0.999m)
(0x00 .. 0x03 0xE7)
iiffff = inverse flattening constant
where: ii = integer part 285..305 (0x01 0x1D .. 0x01 0x31)
ffff = fractional part 0..999,999,999 (0.0..0.999999999)
xx = delta X (0.1 m) -32,768..32,767 (-3276.8..3276.7)
yy = delta Y (0.1 m) -32,768..32,767 (-3276.8..3276.7)
zz = delta Z (0.1 m) -32,768..32,767 (-3276.8..3276.7)
C = checksum
Message length: 25 bytes
Motorola GPS Products - M12+ User's Guide Revision 6.X 09FEB05
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