3.4.2.1. Ashtech Diagnostics

3.4.2.1.1. $PASHR,ATT messages

  • Example: Good data message

$PASHR,ATT,88536.0000,345.9640,0.0390,-0.9052,0.0024,0.0144,0*0E
                        head  , pitch,  roll                 R CC

R = Reacquisition Flag.  0 is good (1 is Bad, i.e. 'yes, I did have to try again')
CC = checksum

  • Example: Bad data message:

$PASHR,ATT,333631.0000,,,,,,*30

(pretty obvious -- "all commas" can't be good)

  • Example: Bad data message:

$PASHR,ATT,74432.0000,35.3421,0.0000,0.0000,0.0013,19150.0205,1*15


NMEA                         $PASHR,ATT
seconds in the week           74432.0000
heading                        35.3421
pitch                        0.0000        <----- bad
roll                         0.0000        <----- bad
mrms                         0.0022
brms                         19150.0205
reacquisition                1             <----- bad
checksum                     *15

3.4.2.1.2. $PASHR,AT2 messages

  • Example: Good data message

$PASHR,AT2,562422.0000,254.6341,0.6977,0.1069,0.0028,0.0263,0,00,0.667,1.7814*65
                       heading , pitch, roll   mrms  brms     R,LL

R = Reacquisition Flag.  0 is good (1 is Bad, i.e. 'yes, I did have to try again')
LL = Last State (0= no search in progress, >0 search in progress)
CC = checksum

  • Example: Bad data message

$PASHR,AT2,562358.0000,254.2164,0.0000,0.0000,0.0000,999.0000,1,00,5.778,1.7030*6E
                       heading , pitch, roll   mrms  brms     R,LL

heading = 254.2164
pitch = 0.0000             <----- bad
roll = 0.0000              <----- bad
mrms = 0.0000              <----- bad
brms = 999.0000            <----- bad
reacquisition flag = 1      Bad is 1 (i.e. 'yes, I did have to try again')
last state = 00             Very Bad is 00 (not trying)

3.4.2.1.3. $GPPAT messages

  • Example: Good data message

$GPPAT,002525.50,4018.48676,N,07108.22871,W,-00029.59,70.4317,000.73,-000.56,0.0030,0.0337,0*54
                                                      heading, pitch,  roll , mrms, brms  ,R CC


R = Reacquisition Flag.  0 is good (1 is Bad, i.e. 'yes, I did have to try again')
CC = checksum

  • Example: Bad data message

$GPPAT,015458.50,0459.6396,S,00000.0563,W,+00032.3,132.940,+00.00,+00.00,0.0052,0.0575,1*57
                                                   heading, pitch,  roll , mrms, brms  ,R CC


heading = 132.94
pitch = +00.00            <-----------  bad
roll = +00.00             <-----------  bad
mrms = 0.0053
brms = 0.0575
reacquisition flag = 1    <-----------  bad

3.4.2.1.4. Indications of bad data:

  1. pitch and roll are zero

  2. reacquisition flag is 1 (i.e. it DID try again)

So, it is often hard to tell from the green panels that there was a problem, because there are barely enough lines.

3.4.2.1.5. checking on UHDAS computer

The following messages might be logged on currents:

  • $PASHR,ATT

  • $PASHR,AT2

  • $GPPAT

Check the UHDAS GUI to see what the message actually is. To see what the ashtech values are (eg. for a $PASHR message), while UHDAS is running, type the following in a terminal window on currents:

showlast.py -a20 | grep PASHR