ADLINK PCI-8164 - Manual (Page 150)

138 Operation Theory
4.7.3 Position Latch
The position latch is different than the position compare function in
the following way: the position compare function triggers a pulse
output via the CMP, when the comparing condition comes into
existence, the position latch function receives pulse inputted via
the LTC, and then captures all data in all counters at that instant
(refer to section 4.4). The latency between the occurring latch sig-
nal and the finish position of the captured data is extremely short
as the latching procedure is done by hardware. Only axes 2 and 3
can perform a position latch function. LTC3 (axis 2) and LTC4
(axis 3) are used to receive latch pulses.
To set the latch logic use _8164_set_ltc_logic().
To obtain the latch values of the counters use
_8164_get_latch_data(AxisNo, CntNo, Pos). The sec-
ond parameter “CntNo” is used to indicate the counter of which the
latched data will be read.
Related function:
X
_8164_set_ltc_logic(),_8164_get_latch_data( : refer to sec-
tion 6.16