Contention between TCNT Byte Write and Increment: If an increment pulse occurs in the T
2
or T
3
state of a TCNT byte write cycle, writing takes priority and TCNT is not incremented. The
TCNT byte that was not written retains its previous value. See figure 10-63, which shows an
increment pulse occurring in the T
2
state of a byte write to TCNTH.
Figure 10-63 Contention between TCNT Byte Write and Increment
ø
Address bus
Internal write signal
TCNT input clock
TCNTH
TCNTL
TCNTH byte write cycle
T
1
T
2
T
3
N
TCNTH address
M
TCNT write data
X
X
X + 1
382
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