Z84C90_12 Datasheet, PDF (38/56 Pages) Zilog, Inc. – KIO Serial/Parallel Counter/Timer

Z84C90 KIO Serial/Parallel Counter/Timer
Product Specification
31
Table 3. DC Characteristics of the Z84C90 (Continued)
Symbol Item
Min
Max
Unit Condition
I_OHD
I_CC
Darlington Drive Current
(Port B and ZC/T00~3)
Power Supply Current*
8 MHz
–1.5
mA V_OH = 1.5V
R_EXT = 390 Ω
15
mA
10 MHz
15
mA
12.5 MHz
15
mA
Note: *Measurement made with output floating over specified temperature and voltage ranges with V_CC = 5 V, V_IH =
V_CC – 0.2 V and V_IL = 0.2 V.
Figure 34 shows the timing of reads and writes for the Z84C90 KIO Peripheral’s I/O
block.
1
Clock
2
3
5
4
A0–A3
CS
6
7
IORQ
6
7
RD
9
D0–D7
8
15
8
10
10 _{Read Cycle}
RD
D0–D7
WT/RDY
Wait Mode
48
WT/RDY
Ready Mode
12
47
49
48
Figure 34. I/O Read/Write Timing (M1 = 1)
11 Write Cycle
PS011804-0612
DC Characteristics