16F84A Microchip Technology, 16F84A Datasheet - Page 14

• Manufacturer Part Number: 16F84A
• Description: 18-pin Enhanced Flash/EEPROM 8-Bit Microcontroller
• Manufacturer: Microchip Technology

PIC16F84A
FIGURE 3-2:
TABLE 3-1
TABLE 3-2
DS35007A-page 14
Address Name
RA0
RA1
RA2
RA3
RA4/T0CKI
Legend: TTL = TTL input, ST = Schmitt Trigger input
05h
85h
Legend: x = unknown, u = unchanged, - = unimplemented read as '0'. Shaded cells are unimplemented, read as '0'
Name
Data
bus
WR
TRIS
WR
PORT
RD PORT
Note: I/O pin has protection diodes to V
TMR0 clock input
PORTA
TRISA
TRIS Latch
Data Latch
D
D
CK
CK
BLOCK DIAGRAM OF PIN RA4
SUMMARY OF REGISTERS ASSOCIATED WITH PORTA
PORTA FUNCTIONS
Bit0
RD TRIS
bit0
bit1
bit2
bit3
bit4
Q
Q
Q
Q
Bit 7
—
—
Q
Buffer Type
Bit 6
—
—
EN
Schmitt
Trigger
input
buffer
EN
TTL
TTL
TTL
TTL
ST
D
V
N
SS
Bit 5
—
—
SS
only.
RA4 pin
Input/output
Input/output
Input/output
Input/output
Input/output or external clock input for TMR0.
Output is open drain type.
RA4/T0CKI
TRISA4
Bit 4
Preliminary
TRISA3
Bit 3
RA3
TRISA2
Bit 2
RA2
TRISA1
Function
Bit 1
RA1
TRISA0
Bit 0
RA0
1998 Microchip Technology Inc.
---x xxxx
---1 1111
Power-on
Value on
Reset
other resets
Value on all
---u uuuu
---1 1111