Z86D73 Datasheet, PDF (30/92 Pages) Zilog, Inc. – 40/44/48-Pin Low-Voltage IR OTP

Z86D73
40/44/48-Pin Low-Voltage IR OTP
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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(D)01h” on page 37). Other
edge detect and IRQ modes are described in Table 9.
Note: Comparators are powered down by entering STOP Mode. For
P31–P33 to be used in a Stop-Mode Recovery (SMR) source,
these inputs must be placed into digital mode.
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Table 9. Pin Assignments
Pin
Pref1
P31
P32
P33
P34
P35
P36
P37
P20
I/O
IN
IN
IN
OUT
OUT
OUT
OUT
I/O
C/T
IN
T8
T16
T8/16
IN
Comp.
RF1
AN1
AN2
RF2
AO1
AO2
Int.
IRQ2
IRQ0
IRQ1
Port 3 also provides output for each of the counter/timers and the AND/OR Logic
(see Figure 14). Control is performed by programming bits D5–D4 of CTR1, bit 0
of CTR0, and bit 0 of CTR2.
PS019402-1103
PRELIMINARY