HD6433937 Datasheet, PDF (219/521 Pages) Hitachi Semiconductor – Hardware Manual

1. Write access
Write access to the upper byte results in transfer of the upper-byte write data to TEMP. Next,
write access to the lower byte results in transfer of the data in TEMP to the upper register byte,
and direct transfer of the lower-byte write data to the lower register byte.
Figure 9-4 shows an example in which H'AA55 is written to TCF.
Write to upper byte
CPU
(H'AA)
Bus
interface
Module data bus
TEMP
(H'AA)
Write to lower byte
CPU
(H'55)
Bus
interface
TCFH
()
TCFL
()
Module data bus
TEMP
(H'AA)
TCFH
(H'AA)
TCFL
(H'55)
Figure 9-4 Write Access to TCF (CPU → TCF)
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