Z80180 Datasheet, PDF (181/326 Pages) Zilog, Inc. – Z8018x Family MPU

Z 8018x Fam ily
M PU Us e r M anual
166
These devices require connection with the Z8X180 synchronous E clock
output. The speed (access time) required for the peripheral devices are
determined by the Z8X180 clock rate. Table 24, and Figure 67 through
Figure 70 define E clock output timing.
Wait States are inserted in Op Code fetch, memory read/write, and I/O
read/write cycles which extend the duration of E clock output High.
During I/O read/write cycles with no Wait States (only occurs during on-
chip I/O register accesses), E does not go High.
Table 24. E Clock Timing in Each Condition
Condition
Duration of E Clock Output High
Op Code Fetch Cycle
Memory Read/Write Cycle
T2 rise - T3 fall
(1.5 Phi + nw x Phi)
I/O read Cycle
1st Tw rise - T3 fall (0.5Phi + nw x Phi)
I/O Write Cycle
NMI Acknowledge 1st MC
INT0 Acknowledge 1st MC
BUS RELEASE mode
SLEEP mode
SYSTEM STOP mode
1st Tw rise - T3 rise
T2 rise - T3 fall
1st Tw rise - T3 fall
Phi fall - Phi fall
In_w x Phi)
(1.5 Phi)
(0.50 + nw x Phi)
(2 Phi or 1 Phi)
Note: nw = the number of Wait States; MC: Machine Cycle
UM005001-ZMP0400