Z86L81 Datasheet, PDF (24/88 Pages) Maxim Integrated Products – 28-Pin Low-Voltage Infrared Microcontrollers

Z86L81/86/98
28-Pin Low-Voltage Infrared Microcontrollers
18
Z89L98
MCU
Pref1
P31
P32
P33
P34
P35
P36
P37
Port 3 (I/O)
R247 = P3M
D1
1 = Analog
0 = Digital
P31 (AN1)
Pref
Dig.
+ ^Comp1
An.
-
P32 (AN2)
P33 (REF2)
+ ^Comp2
-
IRQ2, P31 Data Latch
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 Register Description” on
page 32). Other edge detect and IRQ modes are described in Table 8.
19-4615; Rev 0; 4/09