
1
1
P
P
8
P
Notes
1.
To avoid a ‘latch-up’ effect at power-on, the voltage on any pin (at any time) must not be higher than V
DD
+ 0.5 V or lower than V
SS
0.5 V
respectively.
To prohibit the toggling of the ALE/WE pin (RFI noise reduction) the bit RFI in the PCON register (PCON.5) must be set by software. This bit is
cleared on reset and can be cleared by software. When set, ALE/WE pin will be pulled down internally, switching an external address latch to a
quiet state. The MOVX instruction will still toggle ALE/WE as a normal MOVX. ALE/WE will retain its normal HIGH value during Idle mode and a
LOW value during Power-down mode while in the ‘RFI’ mode. Additionally during internal access (EA = 1) ALE/WE will toggle normally when the
address exceeds the internal program memory size. During external access (EA = 0) ALE/WE will always toggle normally, whether the flag ‘RFI’ is
set or not.
n.a. = not applicable.
2.
3.
P4.0 to P4.7
20, 24,
26, 44,
46, 50, 53
and 57
60, 62,
63, 7, 8,
10, 13
and 16
1, 4, 18,
31, 32,
33, 35,
36, 37, 38
52 and 66
12, 16,
18, 34,
36, 40, 43
and 47
50, 52,
53, 63,
64, 2, 5
and 8
23, 24,
25, 27,
28, 42
and 58
n.a.
(3)
n.a.
n.a.
Port 4: P4.0 to P4.7
; 8-bit quasi-bidirectional I/O port with internal
pull-ups. Port 4 can sink/source 4 LSTTL inputs. It can drive CMOS
inputs without external pull-ups.
P5.0 to P5.7
n.a.
n.a.
n.a.
Port 5: P5.0 to P5.7
; 8-bit quasi-bidirectional I/O port with internal
pull-ups. Port 5 can sink/source 4 LSTTL inputs. It can drive CMOS
inputs without external pull-ups.
n.c.
6, 17, 28
and 39
1, 12, 23
and 34
n.a.
Not connected.
SYMBOL
PIN
(1)
DESCRIPTION
PLCC68
QFP64
PLCC44
QFP44
DIP40