Hitachi H8/3022 Hardware Manual page 508

Bit 7—Software Standby (SSBY): Enables transition to software standby mode. When software
standby mode is exited by an external interrupt, this bit remains set to 1 after the return to normal
operation. To clear this bit, write 0.
Bit 7
SSBY Description
0 SLEEP instruction causes transition to sleep mode
1 SLEEP instruction causes transition to software standby mode
Note: Clear the SWE bit before executing the SLEEP instruction.
Bits 6 to 4—Standby Timer Select (STS2 to STS0): These bits select the length of time the CPU
and on-chip supporting modules wait for the clock to settle when software standby mode is exited
by an external interrupt. If the clock is generated by a crystal resonator, set these bits according to
the clock frequency so that the waiting time (for the clock to stabilize) will be at least 7 ms. See
table 17-3. If an external clock is used, any setting is permitted.
Bit 6 Bit 5
STS2 STS1
0 0
1
1 0
0
1
498
Bit 4
STS0 Description
0 Waiting time = 8192 states
1 Waiting time = 16384 states
0 Waiting time = 32768 states
1 Waiting time = 65536 states
0 Waiting time = 131072 states
1 Waiting time = 1024 states
— Illegal setting
(Initial value)
(Initial value)