Standby-Quick Recovery Mode; Internal I/O Registers - ZiLOG Z8018 Series User Manual

except that the 2
asserted eight clock cycles after the exit conditions are gathered.

STANDBY-QUICK RECOVERY Mode

STANDBY-QUICK RECOVERY mode is an option offered in
STANDBY mode to reduce the clock recovery time in STANDBY mode
17
clock cycles (4 μs at 33 MHz) to 2
from 2
MHz). This feature can only be used when providing an oscillator as
clock source.
To enter STANDBY-QUICK RECOVERY mode:
1. Set bits 6 and 3 to
2. Set the I/O STOP bit (bit 5 of ICR, I/O Address =
3. Execute the SLEEP instruction
When the part is in STANDBY-QUICK RECOVERY mode, the operation
is identical to STANDBY mode except when exit conditions are gathered,
using RESET, BUS REQUEST or EXTERNAL INTERRUPTS. The
clock and other control signals are recovered sooner than the STANDBY
mode.
Note:
If STANDBY-QUICK RECOVERY is enabled, the user must
ensure stable oscillation is obtained within 64 clock cycles

Internal I/O Registers

The Z8X180 internal I/O Registers occupy 64 I/O addresses (including
reserved addresses). These registers access the internal I/O modules
(ASCI, CSI/O, PRT) and control functions (DMAC, DRAM refresh,
interrupts, wait state generator, MMU and I/O relocation).
17
bit wake-up timer is bypassed. All control signals are
and , respectively.
1 1
Family MPU User Manual
6
clock cycles (1.9 μs at 33
) to
3FH
UM005004-0918
Z8018x
41
.
1