Z86E61 Datasheet, PDF (11/44 Pages) Zilog, Inc. – CMOS Z8 16K/32K EPROM MICROCONTROLLER

PRELIMINARY
Z86E61/E63 Z8^® MCU
WITH 16K/32K EPROM
Port 3 (P37-P30). Port 3 is an 8-bit, CMOS compatible four-
fixed input and four-fixed output port. These eight I/O lines
have four-fixed (P33-P30) input and four-fixed (P37-P34)
output ports. Port 3, when used as serial I/O, is pro-
grammed as serial in and serial out, respectively
(Figure 9).
Z86E61
/E63
MCU
Port 3
(I/O or Control)
Figure 9. Port 3 Configuration
Port 3 is configured under software control to provide the
following control functions: handshake for Ports 0 and 2
(/DAV and RDY); four external interrupt request signals
(IRQ3-IRQ0); timer input and output signals (T and T ),
IN
OUT
Data Memory Select (/DM) and EPROM control signals
(P30 = /CE, P31 = /OE, P32 = EPM and P33 = V ).
PP
Pin
I/O
CTC1
P30
IN
P31
IN
T
IN
P32
IN
P33
IN
P34
OUT
P35
OUT
P36
OUT
P37
OUT
T0
T1
Notes:
HS = Handshake Signals
D = Data Available
R = Ready
T_OUT
Table 5. Port 3 Pin Assignments
Int.
P0 HS
P1 HS
P2 HS
UART
Ext
IRQ3
Serial In
IRQ2
D/R
IRQ0
D/R
IRQ1
D/R
R/D
DM
R/D
R/D
Serial Out
IRQ4
IRQ5
EPROM
/CE
/OE
EPM
V
PP
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