Trigger cannot be captured using function keys
Posted: Thu May 05, 2016 12:56 am
Hi,
I'm using LabVIEW API to do my own data acquisition for EOG data. The speedmode is set to 4. As I understand it, I should be getting 282 packets x 4 bytes, per sweep. Ignoring the actual EOG data, channel 0 is the sync word, and channel 1 is the status/trigger. Here are a few samples of the captured data:
-256, -1727987968
-256, -1727987968
-256, -1727987968
-256, -1727987968
-256, -1727987968
-256, -1727987968
-256 == 0xff ff ff 00, which is the sync word
-1727987968 == (binary) 10011001 00000000 11111111 00000000, which is the status / trigger word
If I interpret this correctly, I should ignore the last byte of 0's as it is inserted by the AD converter. So the MSBit = 1, means I have a MK2, bits 19-17 = 100, means speed mode 4.
I was hitting the function keys F1 to F8 repeated during the collection, so I was expecting bits 15 to 8 taking turns becoming 1's instead of always 0's.
I've verified that the ActiveView software can capture the F1-F8 correctly. Do I need to do something different to read the triggers using the LabVIEW API? Please advise.
Thanks and regards,
--Bill
I'm using LabVIEW API to do my own data acquisition for EOG data. The speedmode is set to 4. As I understand it, I should be getting 282 packets x 4 bytes, per sweep. Ignoring the actual EOG data, channel 0 is the sync word, and channel 1 is the status/trigger. Here are a few samples of the captured data:
-256, -1727987968
-256, -1727987968
-256, -1727987968
-256, -1727987968
-256, -1727987968
-256, -1727987968
-256 == 0xff ff ff 00, which is the sync word
-1727987968 == (binary) 10011001 00000000 11111111 00000000, which is the status / trigger word
If I interpret this correctly, I should ignore the last byte of 0's as it is inserted by the AD converter. So the MSBit = 1, means I have a MK2, bits 19-17 = 100, means speed mode 4.
I was hitting the function keys F1 to F8 repeated during the collection, so I was expecting bits 15 to 8 taking turns becoming 1's instead of always 0's.
I've verified that the ActiveView software can capture the F1-F8 correctly. Do I need to do something different to read the triggers using the LabVIEW API? Please advise.
Thanks and regards,
--Bill