Specifications

Counter/Timers
Multiple Latch Command
The Multiple Latch command extends the capabilities of the Count
Latch command. The Multiple Latch command is used to selectively
latch the count and status of any or all counter/timers simultaneously.
This command is the only method of reading the status of a
counter/timer.
Once the status or count is latched with this command, it is unaffected
by further latch commands. The latched data must be read or the
counter/timer reinitialized before the Count Latch and Status Latch
will resume tracking the operation of the Down Counter.
The count and status must be read according to the Read/Write Mode
programmed for the selected counter/timer. Two read operations are
required if the Read/Write Mode specifies two-byte operation and the
status is not latched. The first read is for the low byte of the count and
the second for the high byte. If the status is latched, three read
operations are required with the status being the first byte read,
followed by the low and then the high bytes of the count. One read
operation is all that is needed for single-byte mode, if the status is not
latched. For single-byte operations with latched status, two read
operations are needed, the first for the status and the second for the
data.
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