Z80180 Datasheet, PDF (48/326 Pages) Zilog, Inc. – Z8018x Family MPU

Z 8018x Fam ily
M PU Us e r M anual
33
.
Phi
INT1, NMI
HALT Op Code
Fetch Cycle
T1
T3
T1
HALT mode
T2
T3
Interrupt
acknowledge cycle
T1
T2
A0–A19 HALT Op Code address
HALT Op Code address + 1
HALT
M1
MREQ
RD
Figure 20. HALT Timing Diagram
SLEEP Mode
SLEEP mode is entered by execution of the 2-byte SLP instruction.
SLEEP mode contains the following characteristics:
• The internal CPU clock stops, reducing power consumption
• The internal crystal oscillator does not stop
• Internal and external interrupt inputs can be received
• DRAM refresh cycles stop
• I/O operations using on-chip peripherals continue
• The internal DMAC stop
• BUSREQ can be received and acknowledged
• Address outputs go High and all other control signal outputs become
inactive High
UM005001-ZMP0400