HD6417021 Hitachi Semiconductor, HD6417021 Datasheet - Page 301

• Manufacturer Part Number: HD6417021
• Description: SuperH RISC engine
• Manufacturer: Hitachi Semiconductor

10.6.3
If an increment pulse occurs in the T2 state or T3 state of a TCNT byte write cycle, counter
writing takes priority and the byte data on the side that was previously written is not incremented.
The TCNT byte data that was not written is also not incremented and retains its previous value.
The timing is shown in figure 10.60 (which shows an increment during state T2 of a byte write
cycle to TCNTH).
Contention between TCNT Byte Write and Increment
Figure 10.60 Contention between TCNT Byte Write and Increment
Internal write signal
TCNT input clock
Address
TCNTH
TCNTL
CK
TCNTH byte write cycle by CPU
T1
X
TCNTH address
N
TCNT write data
T2
X + 1
T3
X
M
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