Channel Gain Queue Configuration - ADLINK Technology cPCI-9116 User Manual

Scan with SSH
You can send the SSH_OUT signal on pin 47 of J1 to external
S&H circuits to sample and hold all signals if you want to simulta-
neously sample all channels in a scan, as illustrated in Figure 4-1.
The 'SSH_OUT' signal is sent to external S&H circuits to hold
the analog signal. Users must implement external S&H circuits
on their own to carry out the S&H function. There are no
NOTE:
NOTE:
onboard S&H circuits.
4.2.2

Channel Gain Queue Configuration

Like software polling acquisition mode, the channel, gain, and
input configurations (single-end, differential, and U_CMMD) must
also be specified in the hardware Channel Gain Queue under
scan acquisition mode. See "Channel Gain Queue Configuration"
on page 20. Note that in scan acquisition mode, the number of
entries in the channel gain queue is normally equivalent to the
value of DIV_counter (that is, the numbers of samples per scan).
Example:
Set
SI2_counter = 240
SI_counter = 960
SC_counter = 3
DIV_counter = 4
Timebase = Internal clock source
Channel entries in the Channel Gain Queue: ch1, ch2, ch0, ch2
Then
Acquisition sequence of channels: 1, 2, 0, 2, 1, 2, 0, 2, 1, 2, 0, 2.
Sampling Interval = 240/24M s = 10 us
Scan Interval = 960/24M s = 40 us Equivalent sampling rate of
ch0, ch1: 25kHz Equivalent sampling rate of ch2: 50kHz
Operation Theory
cPCI-9116
23