User`s guide

Chapter 5 - I/O Commands
DEFINE USER DATUM MESSAGE (@@Ap)
Motorola Binary Format
Query current User Defined Datum Parameters:
@@ApdxxxxxxxxxxxxxxxxxC<CR><LF>
where:
d = user datum ID: 50
xxxxxxxxxxxxxxxxx = 17 bytes, all 0x00
C = 0x31
Message length: 25 bytes
Complete hex string to query current User Defined Datum Parameters:
0x40 40 41 70 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 31 0D 0A
Change current User Defined Datum Parameters:
@@ApdsssffiiffffxxyyzzC<CR><LF>
where:
d = datum ID 50
sssff = semi-major axis (m)
sss = integer part 6,000,000..7,000,000
ff = fractional part 0..999 (0.0..0.999)
iiffff = inverse flattening
ii = integer part 285..305
ffff = fractional part 0..999,999,999 (0.0..0.999999999)
xx = delta X (0.1 m resolution) -32,768..32,767 (-3276.8..3276.7)
yy = delta Y (0.1 m resolution) -32,768..32,767 (-3276.8..3276.7)
zz = delta Z (0.1 m resolution) -32,768..32,767 (-3276.8..3276.7)
C = checksum
Message length: 25 bytes
Response to either command:
@@ApdsssffiiffffxxyyzzC<CR><LF>
where:
d = datum ID 50
sssff = semi-major axis (m)
sss = integer part 6,000,000..7,000,000
ff = fractional part 0..999 (0.0..0.999)
iiffff = inverse flattening
ii = integer part 285..305
ffff = fractional part 0..999,999,999 (0.0..0.999999999)
xx = delta X (0.1 m resolution) -32,768..32,767 (-3276.8..3276.7)
yy = delta Y (0.1 m resolution) -32,768..32,767 (-3276.8..3276.7)
zz = delta Z (0.1 m resolution) -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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