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Rebuild 
Calibration 

C/67 

None 

The  calibration  is  rebuilt  for the current temperature, using the 
active microDAQ settings 

Filter  

F/70 

0 - Off 
 
1 -  2 
2 -  4 
3 -  8 
4 -  16 
5 -  32 
6 -  64 
7 -  128 
8 -  256 
9 -  512 
10 - 1024 
11 - 2048 
12 - 4096 
13 - 8192 
14 - 16384 
15 - 32768 
16 - 65536 
 
17 - Reset on Ouptut 

Adjust the output filter setting that is applied after the calibration 
within  the  microDAQ.    If  switching  the  data  delivery  rate 
between slow and fast values, it may be desirable to adjust the 
amount  of  output  filtering  accordingly.    Also  the  average 
between delivery option may be chosen through this command. 

The  value  of  the  parameter  reflects  the  number  of  samples  in 
the  output  moving  average.    In  the  case  of  'Reset  on  Output', 
the measured pressure value is averaged over the time between 
data delivery cycles. 

Rezero and 
Rebuild 

G/71 

None 

Requests  a  rezero  followed  by  a  calibration  table  rebuild,  with 
the  calculated  zero  offsets  being  applied  to  the  calibration 
data..  Note  these  rezero  offsets  are  separate  from  any  normal 
rezero that may be performed afterwards. 

Rate 

V/86 

byte = 0xab 
 
a = 0 RS232 
a = 1 TCP 
a = 2 CAN 
a = 3 Internal RAM 
 
For RS232 : 
b = 0 :  Off 
b = 1 :  20 Hz 
b = 2 :  10 Hz 
b = 3 :  5 Hz 
b = 4 : 2 Hz 
b = 5 : 1 Hz 
 
For TCP : 
b = 0 :  Off 
b = 1 : 1000Hz 
b = 2 :  625Hz 
b = 3 :  500 Hz 
b = 4 :  400 Hz 
b = 5 :  312 Hz 
b = 6 :  225 Hz 
b = 7 :  200 Hz 
b = 8 :  150 Hz 
b = 9 :  100 Hz 
b = 10 : 50 Hz 
b = 11 : 25 Hz 
b = 12 :  20 Hz 
b = 13 : 10 Hz 
b = 14 : 5 Hz 
b = 15 : 1 Hz 
 
For CAN & Internal 
RAM: 
b = 0 :  Off 
b = 1 :  1000 Hz 

Adjust  the  data  delivery  rate  for  each  communication  channel.  
The  upper  nibble  of  the  parameter  byte  selects  which 
communication channel, while the lower selects its data rate. 

CAN  &  Internal  RAM  ‘comms’  have  the  same  available  data 
rates. 

Summary of Contents for microDAQ

Page 1: ...Folgate Road North Walsham Norfolk NR28 0AJ ENGLAND Tel 01692 500555 Fax 01692 500088 microDAQ Pressure Scanner Acquisition System USER PROGRAMMING GUIDE e mail info chell co uk Visit the Chell websit...

Page 2: ...ified in this manual may impair the user s protection Chell Document No 900167 Issue 1 3 ECO 1270 Date 28th November 2014 Chell s policy of continuously updating and improving products means that this...

Page 3: ...ol 7 4 1 4 Control Via RS232 7 4 1 5 Data Rate 7 4 2 TCP 8 4 2 1 Overview 8 4 2 2 Connection 8 4 2 3 TCP Protocol 8 4 2 4 TCP Data Rate 8 4 2 5 Control Via TCP 9 4 3 CAN 9 4 3 1 Overview 9 4 3 2 CAN B...

Page 4: ...received command may be acknowledged if required The following sets out the essentials of the command protocol the data packet format for all channels in addition to the message identifier arrangemen...

Page 5: ...ASCII The response to the command is to echo back the string Test command rxd ok n where n is the value of the parameter byte This may be checked from a terminal program by typing dC ie byte values 6...

Page 6: ...pressure value is averaged over the time between data delivery cycles Rezero and Rebuild G 71 None Requests a rezero followed by a calibration table rebuild with the calculated zero offsets being app...

Page 7: ...rnal RAM Disable the data delivery for the chosen channel Get Status 63 0 Short 1 With temp 2 Full 3 Pressure reading 4 Temp readings 5 Excitation reading 6 Hall sensor read 7 Firmware ID 8 Unit seria...

Page 8: ...channels A calibration table rebuild is then performed Hardware Trigger T 84 byte 0xab a 0 Disable a 1 Enable b 0 RS232 b 1 TCP b 2 CAN b 3 Internal RAM b 4 Internal RAM stop on full Enables or disabl...

Page 9: ...in ascending order as comma delimited ASCII engineering units ie degrees C The full status data contains the above followed by fields for the setup options of the microDAQ Each field is comma delimite...

Page 10: ...ations bandwidth as well as less processor overhead within the microDAQ it is recommended that engineering unit conversions be applied at the client Protocol Example data format Note 16 bit LE 0x00 0x...

Page 11: ...ing to 10kHz from the default maximum 20kHz due to internal issues regarding string handling The 16 bit little ended protocol is most efficient from the microDAQ s viewpoint the data being calibrated...

Page 12: ...account to avoid losing data Please note that if streaming at high data rates it is essential that a good network infrastructure is used It is recommended that any streaming is performed over a priva...

Page 13: ...ty to avoid overlap of message identifiers in a multiple microDAQ installation Data are two bytes unsigned scaled to full scale ie 0x0000 might represent 5psi 0xffff 5psi The data are user selectable...

Page 14: ...MSB CH18 MSB CH22 MSB CH26 MSB CH30 MSB 2 CH2 LSB CH6 LSB CH10 LSB CH14 LSB CH18 LSB CH22 LSB CH26 LSB CH30 LSB 1 CH1 MSB CH5 MSB CH9 MSB CH13 MSB CH17 MSB CH21 MSB CH25 MSB CH29 MSB 0 Ch1 LSB Ch5 LSB...

Page 15: ...The offset from the base identifier may be selected as being 0x10 0x20 0x30 0x40 or 0x50 For example the base data message identifier of 0x220 might be set up to receive commands over CAN on message...

Page 16: ...on the selected CAN message type single message or multiple message IDs as detailed in section 4 3 3 above In addition to the above an internal RAM dump sends a 9 or 6 byte header which is sent as soo...

Page 17: ...ion of the standard command set and can be transmitted all through the same comms connection These commands change the valves accordingly to perform a zero function or a purge function and also to sim...

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