Measurement Computing BTH-1208LS - Manual (Page 11)

11
Chapter 3
Functional Details
Analog input acquisition modes
The BTH-1208LS can acquire analog input data in three different modes – software paced, continuous scan, and
BURSTIO.
Software paced mode
In software paced mode you can acquire one analog sample at a time. You initiate the A/D conversion by
calling a software command. The analog value is converted to digital and returned to the computer. You repeat
this procedure until you have the total number of samples that you want from one channel.
 When communicating over a Bluetooth connection, the typical throughput sample rate in software paced
mode is 10 S/s (system-dependent).
 When communicating over a USB connection, the typical throughput sample rate in software paced mode
is 250 S/s (system-dependent).
Hardware paced mode
In hardware paced mode you can acquire data from up to eight channels. The analog data is acquired and
converted to digital values until you stop the scan.
 When communicating over a Bluetooth connection, the maximum sample rate of 1024 S/s is an aggregate
rate. The total acquisition rate for all channels cannot exceed 1024 S/s. The following table lists the sample
rates when scanning from one to eight channels in Bluetooth mode.
Maximum per channel sample rate in Bluetooth mode
# channels scanned Sample rate (S/s)
1 1024
2 512
3 341.33
4 256
5 204.8
6 170.67
7 146.28
8 128
 When communicating over a USB connection, the maximum sample rate of 47 kS/s is an aggregate rate.
The total acquisition rate for all channels cannot exceed 47 kS/s. Data is transferred in blocks of 32 samples
from the device to the memory buffer on your computer.
The following table lists the sample rates when scanning from one to eight channels in USB mode.
Maximum per channel sample rate in USB mode
# channels scanned Sample rate (kS/s)
1 47
2 23.5
3 15.67
4 11.75
5 9.40
6 7.83
7 6.70
8 5.88