Problem with Sigfox Payload

[bucknall]

@Jiemde

That looks to be fine - What does the Sigfox Backend give you, instead of the data you're expecting? Also as @livius has suggested, what GPS are you using?

@livius We'll be adding the CRC check and utilization of other GPS messages shortly. Thanks for your patience!

[Jiemde]

@livius
Yes the coordinates are right !
When you take the 4 first bytes of the payload seeing in Sigfox for example " d5174d00" and you enter this part of payload in an "Lat=struct.unpack('i', b'\0xd5\0x17\0x4d\0x00') you will retreive the good Latitude.
I think that teh code is sending the good coordinates, but I don't find how to configure the payload display in "device type" in the Sigfox backend !

Regards
jiemde

[livius]

@Jiemde
now it is much cliear where you have the problem

i do not know sigfox much but this format is valid?
int1::4 int2::4

i suppose you need
int1:uint::4 int2:uint::4

[Jiemde]

@bucknall
The Sigfox backend display "d5174d0072b50800"
The decoding payload "int1::4 int2::4", display 2 integer but not the good one!

image url)

[livius]

@Jiemde
sorry mistake
int1:uint::32 int2:uint::32

[Jiemde]

@livius
Yes of course! :))

[Jiemde]

@livius
Had already tested this but not the good result.

jiemde

[livius]

@Jiemde
what are results - maybe this hint something

[Jiemde]

@livius
Here is the printscreen

[livius]

@Jiemde

sadly i do not have sipy to test self but
looking at your values i see that you have variation on most significant bits
try then this:
int1:uint::32:little-endian int2:uint::32:little-endian

if this does not help then post output from corrds recived by pytrack + output packed
and what you got for this frames on sigfox

[Jiemde]

@livius
No change in the displaying data.
As I don't have my SiPy/Pytrack with me at my office, I will reply this evening to your other question.

best regards
jiemde

[Jiemde]

@livius
You will find the output you ask:

def sendtosigfox():

datatosend = struct.pack('ii', int(coords[0]*100000),  int(coords[1]*100000))
print('sigfox send: {}\n'.format(datatosend))
size1=struct.calcsize('i')
size2=struct.calcsize('ii')
print('calcsize: ', size1, size2)

sigfox = Sigfox(mode=Sigfox.SIGFOX, rcz=Sigfox.RCZ1)
s = socket.socket(socket.AF_SIGFOX, socket.SOCK_RAW)
s.setblocking(True)
s.setsockopt(socket.SOL_SIGFOX, socket.SO_RX, False)

s.send(datatosend)
s.setblocking(False)
s.close()

while True:
acc = LIS2HH12(py)
roll = acc.roll()
print('X= ', roll)
pitch = acc.pitch()
print('Y= ', pitch)
yaw = acc.yaw()
print('Z= ', yaw)
time.sleep(1)
gps = L76GNSS(py)
coords = gps.coordinates()
print(coords)
sendtosigfox()
time.sleep(600)

The output in Atom/Pymakr:

The output in Sigfox backend

Regards
Jiemde

[livius]

@Jiemde
can you add before struct.pack

print(coords)
or
print(str(coords)) #if above not work cast first to string

[livius]

@Jiemde

is this really your position?

b'\xc8\x17M\x00k\xb5\x08\x00'
(5052360, 570731)

will be really helpfull to see

print(coords)

as mentioned below

[Jiemde]

@livius
Yes it 's my position !
The coords are displayed just before the "sigfox send: " on the output in Atom/pymakr picture.

(50.5236, 5.707314)

Jiemde

[livius]

@Jiemde
Ahh i see :) I have missed it.

and i see problem (previously i have thinked in opposite direction)

try do this (one of this should do the trick)

datatosend = struct.pack('>II', int(coords[0]*100000),  int(coords[1]*100000))

or not and on sigfox backend (i do not know why little not do the job and suppose that only above line will work for you)

int1:uint::32:big-endian int2:uint::32:big-endian

[Jiemde]

@livius
Hi livius, That's work!, now I need to understand how work the "format" of the "pack" function and specialy "little and big-endian.

Best regards
Jiemde