Z86E30/E31/E40
Z8 4K OTP Microcontroller
Zilog
Table 9. Port 3 Pin Assignments
Pin
I/O
CTC1
Analog
Interrupt
P0 HS
P1 HS
P2 HS
Ext
P30
P31
IN
IN
IRQ3
IRQ2
1
T
AN1
D/R
IN
P32
P33
P34
P35
P36
IN
AN2
REF
IRQ0
IRQ1
D/R
R/D
IN
D/R
R/D
OUT
OUT
OUT
AN1-Out
/DM
T
R/D
OUT
P37
OUT
An2-Out
Comparator Inputs. Port 3, P31, and P32, each have a
comparator front end. The comparator reference voltage
P33 is common to both comparators. In analog mode, P31
and P32 are the positive input of the comparators and P33
is the reference voltage of the comparators.
■ The pre-drivers slew rate reduced to 10 ns typical.
■ Low EMI output drivers have resistance of 200 Ohms
(typical).
■ Low EMI Oscillator.
Auto Latch. The Auto Latch puts valid CMOS levels on all
CMOS inputs (except P33-P31) that are not externally
driven. Whether this level is 0 or 1, cannot be determined.
A valid CMOS level, rather than a floating node, reduces
excessive supply current flow in the input buffer. Auto
Latches are available on Port 0, Port 2, and P30. There
are no Auto Latches on P31, P32, and P33.
■ Internal SCLK/TCLK= XTAL operation limited to a
maximum of 4 MHz - 250 ns cycle time, when Low EMI
Oscillator is selected and system clock (SCLK = XTAL,
SMR Reg. Bit D1 =1).
■ Note for emulation only:
Do not set the emulator to emulate Port 1 in low EMI
mode. Port 1 must always be configured in Standard
Mode.
Low EMI Emission. The Z86E40 can be programmed to
operate in a low EMI Emission Mode in the PCON register.
The oscillator and all I/O ports can be programmed as low
EMI emission mode independently. Use of this feature re-
sults in:
DS97Z8X0500
P R E L I M I N A R Y
31
ZILOG [ ZILOG, INC. ]
