Z84C2008PEG Zilog, Z84C2008PEG Datasheet - Page 33

• Manufacturer Part Number: Z84C2008PEG
• Description: IC 8MHZ Z80 CMOS PIO 40-DIP
• Manufacturer: Zilog
• Series: Z80r

Specifications of Z84C2008PEG

• Processor Type: Z80
• Features: Low Power CMOS
• Speed: 8MHz
• Voltage: 5V
• Mounting Type: Through Hole
• Package / Case: 40-DIP (0.620", 15.75mm)
• Cpu Speed: 8MHz
• Digital Ic Case Style: DIP
• No. Of Pins: 40
• Supply Voltage Range: 5V
• Operating Temperature Range: -40°C To +100°C
• Svhc: No SVHC (18-Jun-2010)
• Rohs Compliant: Yes
• Processor Series: Z84C2xx
• Core: Z80
• Data Bus Width: 8 bit
• Maximum Clock Frequency: 8 MHz
• Number Of Programmable I/os: 16
• Operating Supply Voltage: 0 V to 5 V
• Maximum Operating Temperature: + 100 C
• Mounting Style: Through Hole
• Minimum Operating Temperature: - 40 C
• Base Number: 84
• Clock Frequency: 8MHz
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

UM008005-0205
A
D
15
7
MREQ
RFSH
WAIT
— D
— A
CLK
RD
M1
Memory Read Or Write
0
0
segments from being gated onto the data bus. The MREQ signal during
refresh time should be used to perform a refresh read of all memory
elements. The refresh signal can not be used by itself because the refresh
address is only guaranteed to be stable during MREQ time.
Figure 5.
Figure 6 illustrates the timing of memory read or write cycles other than an
Op Code fetch cycle. These cycles are generally three clock periods long
unless wait states are requested by the memory through the WAIT signal.
The MREQ signal and the RD signal are used the same as in the fetch cycle.
In a memory write cycle, the MREQ also becomes active when the address
bus is stable so that it can be used directly as a chip enable for dynamic
memories. The WR line is active when data on the data bus is stable so that
T
PC
1
Instruction Op Code Fetch
T
2
M1 Cycle
IN
T
3
Refresh Address
T
4
T
User’s Manual
1
Z80 CPU
Overview
13