Z86D86 Datasheet, PDF (23/80 Pages) Zilog, Inc. – 28-Pin Low-Voltage OTP Microcontroller

Z86D86
28-Pin Low-Voltage OTP Microcontroller
15
timers. P31, P32, and P33 are standard CMOS inputs; P34, P35, P36, and P37
are push-pull outputs.
P31 (AN1)
Pref
Z86D86
MCU
Pref1
P31
P32
P33
Port 3 (I/O)
P34
P35
P36
P37
R247 = P3M
D1
1 = Analog
0 = Digital
DIG.
Comp1
+
AN.
–
IRQ2, P31 Data Latch
P32 (AN2)
P33 (Ref2)
Comp1
+
–
IRQ0, P32 Data Latch
From Stop Mode
Recovery Source of SMR
IRQ1, P33 Data Latch
Figure 8. Port 3 Configuration
Two on-board comparators process analog signals on P31 and P32 with refer-
ence to the voltage on Pref1 and P33. The analog function is enabled by program-
ming the Port 3 Mode Register (bit 1). P31 and P32 are programmable as rising,
falling, or both edge-triggered interrupts (IRQ register bits 6 and 7). Pref1 and P33
are the comparator reference voltage inputs. Access to the counter/timer
edge-detection circuit is through P31 or P20 (see “CTR1 Counter/Timer T8 and
PS008905-0105
PRELIMINARY