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
Module data bus
Bus
interface
CPU
(H'AA)
TEMP
(H'AA)
TCFH
TCFL
(
)
(
)
Write to lower byte
Module data bus
Bus
interface
CPU
(H'55)
TEMP
(H'AA)
TCFH
(H'AA)
TCFL
(H'55)
Figure 9-4 Write Access to TCR (CPU Æ TCF)
208
ETC [ ETC ]
