Specifications

Counter/Timers
OPERATION
Reset
The TCU registers are not initialized to a default state after power on
or reset.
Count Latch
Command
The count of any counter/timer can be read at any time. The Count
Latch command must be used to guarantee accurate results. Without
the Count Latch command, the count may change during the read
operation and the data will be undefined. After the latch command is
specified in the Mode register, the present value of the Down Counter
is latched into the Count Latch. This value remains in the latch until it
is read by the CPU or the counter/timer is reinitialized. More than one
latch command can be used to latch more than one counter/timer at a
time.
The count latched at the time of a latch command will not be changed
if a second latch command is specified for the same counter/timer
before the count is read by the CPU.
The count must be read according to the programmed Read/Write
Mode. If the Read/Write Mode specifies two-byte operation, two read
operations from the Count register are required, the first for the low
byte and the second for the high byte. If the Read/Write Mode is not
programmed for two-byte operation, only one read operation is
needed.
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