Z84C90_12 Datasheet, PDF (46/56 Pages) Zilog, Inc. – KIO Serial/Parallel Counter/Timer

Z84C90 KIO Serial/Parallel Counter/Timer
Product Specification
39
Table 5. AC Characteristics of the Z84C90 (Continued)
8 MHz
10MHz^1,6 12.5MHz^1,6
No. Symbol
Parameter
Min Max Min Max Min Max U/M
Bus Interface Timing (continued)
20 TdIEIf(IEOf) IEI Fall to IEO Fall Delay³
21 TdIEIf(IEOr) IEI Rise to IEO Rise Delay
(after ED Decode)³
22 TsIEI(Cf)
IEI to Clock Fall Setup (for 4D
Decode)
23 TsIOr(Cf)
IORQ Rise to Clock Fall Setup 
(to activate RDY on next clock)
160
150
125 ns
160
150
125 ns
50
40
30
ns
100
100
100
ns
PIO Timing
24 TdCf(RDYr) Clock Fall to RDY Rise Delay
100
100
100 ns
25 TdCf(RDYf) ClockFall to RDYFall Delay
100
100
ns
26 TwSTB
STB Pulse Width
100
80
60
ns
27 TsSTBr(Cf) STBRise to ClockFall Setup
100
100
ns
(to activate RDY on next clock
cycle)
28 TdIOf(PD)
IORQFall to Port Data Valid
(Mode 0)
140
120
110 ns
29 TsPD(STBr) Port A,B Data to STB Rise Setup 140
75
75
ns
Time (Mode 1)
30 TdSTBI(PD) STB Fall to Port A,B Data Valid
Delay (Mode 2)
150
120
110 ns
31 TdSTBr(PDz) STB Rise to Port Data Float Delay
140
120
110 ns
(Mode 2)
32 TdPD(INTf) Port Data Match to INT Fall Delay
250
200
160 ns
(Mode 3)
33 TdSTBr(INTf) STB Rise to INT Fall Delay
290
220
190 ns
34 TsPD(RIf)
PIA Port Data to RD, IORQ Fall
Setup
TBD
TBD
TBD –
Notes:
1. Maximum SIO data rate is f_CLOCK ÷ by 5, in which f_CLOCK = 1 ÷ T_CC.
2. For a Z80 CPU operating above 8MHz, one wait state is required to meet this parameter.
3. These daisy chain parameters include contributions from the PIO, SIO and CTC cells, and vary slightly
depending on how they are ordered by the KIO Command Register.
4. Counter mode only; when using a cycle time less than 3 TcC, parameter #37 must be met.
5. Units are TcC.
6. If the CPU is a Z80 CPU and if it is required to have multiple Z80 peripherals in the system, then the time period
between M1 to IORQ must be extended.
7. Any open-drain output must add a Register-Capacitor (RC) time constant to the specification value.
PS011804-0612
AC Characteristics