p87c770 ETC-unknow, p87c770 Datasheet - Page 30

• Manufacturer Part Number: p87c770
• Description: Microcontrollers Ntsc With On-screen Display Closed Caption
• Manufacturer: ETC-unknow

Philips Semiconductors
14.3
Port 3 is an 8-bit port which can be configured as eight bidirectional port lines (P3.0 to P3.7) or as two external interrupts
(INT0 and INT1), two timer/counter inputs (T0 and T1) and the two I
P3.7 have no alternative functions.
To configure these pins as alternative functions, the corresponding bit in the Port 3 latch (P3) should be programmed to
a logic 1 and the corresponding bit in SFR IEN0 also set to a logic 1.
14.3.1
Table 37 Port 3 Latch (SFR address B0H)
Table 38 Description of P3 bits
1999 Jun 11
Microcontrollers for NTSC TVs with On-Screen
Display (OSD) and Closed Caption (CC)
P37
BIT
7
7
6
5
4
3
2
1
0
Port 3 pin function selection
P
ORT
3 L
SYMBOL
ATCH
P36
P37
P36
P35
P34
P33
P32
P31
P30
6
(P3)
No alternative function available.
When P35 = 1, pin 50 is used as SDA if the I
Otherwise pin 50 is general I/O port line P3.5.
When P34 = 1, pin 49 is used as SDL if the I
Otherwise pin 49 is general I/O port line P3.4.
When P33 = 1, pin 48 is used as Timer 1 input if the ET1 bit in SFR IEN0 is a logic 1.
Otherwise pin 48 is general I/O port line P3.3.
When P32 = 1, pin 47 is used as external interrupt INT0 if the EX0 bit in SFR IEN0 is a
logic 1. Otherwise pin 47 is general I/O port line P3.2.
When P31 = 1, pin 46 is used as Timer 0 input if the ET0 bit in SFR IEN0 is a logic 1.
Otherwise pin 46 is general I/O port line P3.1.
When P30 = 1, pin 45 is used as external interrupt INT1 if the EX1 bit in SFR IEN0 is a
logic 1. Otherwise pin 45 is general I/O port line P3.0.
P35
5
P34
4
30
P33
3
DESCRIPTION
2
C-bus lines (SDA and SCL). Port lines P3.6 and
2
2
CE bit in SFR P1SEL is a logic 1.
CE bit in SFR P1SEL is a logic 1.
P32
2
P8xCx70 family
P31
1
Product specification
P30
0