Chapter 4
Functional Details
Theory of operation - analog input acquisition modes
The miniLAB 1008 can acquire analog input data in three different modes – software
paced, continuous scan, and burst scan.
Software paced mode
In software paced mode, the miniLAB 1008 gathers data in a single acquisition or as a
group of single acquisitions. An analog-to-digital conversion is initiated with a software
command, and the single data point result is returned to the host. This operation may be
repeated until the required number of samples is obtained for the channel (or channels)
in use. Software pacing is limited by the 20 mS round-trip requirement of a USB
interrupt-type endpoint operation. This yields a maximum throughput in software paced
mode of 50 S/s.
Continuous scan mode
In continuous scan mode, the miniLAB 1008 gathers data in a single-channel or multi-
channel sequence. This sequence converts, transfers, and stores data to a user buffer
until the scan is stopped. In this mode, digitized data is continuously written to an on-
board FIFO buffer. This FIFO is serviced in blocks as the data is transferred from the
miniLAB 1008 to the user buffer in the host PC.
The maximum continuous scan rate of 1.2 kS/s is an aggregate rate. The total acquisition
rate for all channels cannot exceed 1.2 kS/s. You can acquire data from one channel at
1.2 kS/s, two channels at 600 S/s and four channels at 300 S/s. You can start a
continuous scan with either a software command or with an external hardware trigger
event.
Burst scan mode
In burst scan mode, the miniLAB 1008 gathers data using the full capacity of its 4K
sample FIFO buffer. You can initiate a single acquisition sequence of one or more
channels by either a software command or an external hardware trigger. The captured
data is then read from the FIFO and transferred to a user buffer in the host PC.
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