HD6412340 HITACHI [Hitachi Semiconductor], HD6412340 Datasheet - Page 376

• Manufacturer Part Number: HD6412340
• Description: H8S/2345 F-ZTAT Hardware Manual
• Manufacturer: HITACHI [Hitachi Semiconductor]

Status Flag Clearing Timing: After a status flag is read as 1 by the CPU, it is cleared by writing
0 to it. When the DTC is activated, the flag is cleared automatically. Figure 9.46 shows the timing
for status flag clearing by the CPU, and figure 9.47 shows the timing for status flag clearing by the
DTC.
ø
Address
Status flag
Interrupt
request
signal
ø
Address
Write signal
Status flag
Interrupt
request
signal
Figure 9.47 Timing for Status Flag Clearing by DTC Activation
Figure 9.46 Timing for Status Flag Clearing by CPU
TSR write cycle
Source address
T1
TSR address
T1
read cycle
DTC
T2
T2
T1
write cycle
Destination
address
DTC
T2
359