PL1000 library in Python2.7 on RaspberryPi (Raspbian)

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KrisHunt
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Joined: Mon Mar 28, 2016 7:45 am

PL1000 library in Python2.7 on RaspberryPi (Raspbian)

Post by KrisHunt »

Hi, I'm having difficulty using the pl1000.SetInterval function when trying to get data from my Picolog 1216. I suspect the 'channel' array format is incorrect as it is giving a return code decimal 16. Can anyone help with this?
Thanks!

Code: Select all

import ctypes
from ctypes import *
from array import array

c_handle = c_int16()
maxvalue = c_int16()
reqd = c_int16()

zstr='abcdefghijklmnop'
testlib = ctypes.CDLL('/opt/picoscope/lib/libpl1000.so')
a=testlib.pl1000OpenUnit( byref(c_handle))
print a, c_handle

a=testlib.pl1000MaxValue(1,byref(maxvalue))
print maxvalue

dat1=c_uint * 16
channel = dat1(1, 2,3,4,5,6,7,8,9,10,11,12,13,14,15,16)
print channel
b=testlib.pl1000GetUnitInfo(1,zstr,100,byref(reqd),1)
print b, zstr
b=testlib.pl1000GetUnitInfo(1,zstr,100,byref(reqd),2)
print b, zstr
b=testlib.pl1000GetUnitInfo(1,zstr,100,byref(reqd),3)
print b, zstr
b=testlib.pl1000GetUnitInfo(1,zstr,100,byref(reqd),4)
print b, zstr
b=testlib.pl1000GetUnitInfo(1,zstr,100,byref(reqd),5)
print b, zstr
b=testlib.pl1000GetUnitInfo(1,zstr,100,byref(reqd),6)
print b, zstr

b=testlib.pl1000SetInterval(1,10000,5,byref(channel),16)
print b, channel

a=testlib.pl1000CloseUnit( byref(c_handle))
print a
The output I'm getting is:
0 c_short(1)
c_short(4095)
<__main__.c_ulong_Array_16 object at 0x75abf850>
0 USB 1.1
0 1
0 PicoLog1216
0 AS920/025
0 17May13
0 PICOPP.SYS V1.0
16 <__main__.c_ulong_Array_16 object at 0x75abf850>
3

Martyn
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Re: PL1000 library in Python2.7 on RaspberryPi (Raspbian)

Post by Martyn »

I won't be able to check until I am in the office tomorrow but I would try 0 to 15 for the channels.
Martyn
Technical Support Manager

KrisHunt
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Joined: Mon Mar 28, 2016 7:45 am

Re: PL1000 library in Python2.7 on RaspberryPi (Raspbian)

Post by KrisHunt »

Thank you,
I think you're right
but unfortunately the result code is the same.
:(

Martyn
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Re: PL1000 library in Python2.7 on RaspberryPi (Raspbian)

Post by Martyn »

Channel enumerations go from 1 to 16, so it is probaby your array that is the problem

You may wish to check out this topic using Python for the USB TC08. It uses numpy which may be the way to go.
Martyn
Technical Support Manager

KrisHunt
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Posts: 0
Joined: Mon Mar 28, 2016 7:45 am

Re: PL1000 library in Python2.7 on RaspberryPi (Raspbian)

Post by KrisHunt »

Thanks, but unfortunately the numpy code gives the same results.
:(

Code: Select all

import ctypes
import numpy as np
from ctypes import *
maxvalue = c_int16()
device = c_int16()
mydll = ctypes.CDLL('/opt/picoscope/lib/libpl1000.so')
a=mydll.pl1000OpenUnit( byref(device))
print a, device

a=mydll.pl1000MaxValue(device,byref(maxvalue))
print a, maxvalue

channel = np.zeros((4,), dtype=np.intc)

channel[0]=1
channel[1]=2
channel[2]=3
channel[3]=4
b=mydll.pl1000SetInterval(device,10000,20,channel.ctypes.data,4)
print b
print channel[0],channel[1],channel[2],channel[3]
The new output:
0 c_short(1)
0 c_short(4095)
16
1 2 3 4

Martyn
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Posts: 3860
Joined: Fri Jun 10, 2011 8:15 am
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Re: PL1000 library in Python2.7 on RaspberryPi (Raspbian)

Post by Martyn »

I don't have anything to test this on , but I think you will need

Code: Select all

us_for_block = c_int32()
us_for_block = 10000

b=mydll.pl1000SetInterval(device,byref(us_for_block),20,byref(channel.ctypes.data),4)
The driver will need to be able to write back into the two byref parameters
Martyn
Technical Support Manager

KrisHunt
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Posts: 0
Joined: Mon Mar 28, 2016 7:45 am

Re: PL1000 library in Python2.7 on RaspberryPi (Raspbian)

Post by KrisHunt »

Thanks for your help, but couldn't get block data configured properly, always the same channel error.
Did get the getsingle value working though so not a total loss. Thanks again!

Code: Select all

for i in range(1, 16):
    b=mydll.pl1000GetSingle(device,i,value.ctypes.data)

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