PIC17C7XX_13 Datasheet, PDF (73/306 Pages) Microchip Technology – High-Performance 8-bit CMOS EPROM Microcontrollers with 10-bit A/D

FIGURE 10-3:
RA3 BLOCK DIAGRAM
Peripheral Data In
D
Q
Data Bus
EN
PIC17C7XX
FIGURE 10-4:
RA4 AND RA5 BLOCK
DIAGRAM
Serial Port Input Signal
Data Bus
Q
D
RD_PORTA
(Q2)
RD_PORTA
(Q2)
Serial Port Output Signals
Q CK
'1'
WR_PORTA
(Q4)
SDA Out
SSP Mode
Note: I/O pin has protection diodes to VSS.
OE = SPEN,SYNC,TXEN, CREN, SREN for RA4
OE = SPEN (SYNC+SYNC, CSRC) for RA5
Note: I/O pins have protection diodes to VDD and VSS.
TABLE 10-1: PORTA FUNCTIONS
Name
Bit0 Buffer Type
Function
RA0/INT
bit0
RA1/T0CKI
bit1
RA2/SS/SCL bit2
RA3/SDI/SDA bit3
RA4/RX1/DT1 bit4
RA5/TX1/CK1 bit5
ST
Input or external interrupt input.
ST
Input or clock input to the TMR0 timer/counter and/or an external interrupt
input.
ST
Input/output or slave select input for the SPI, or clock input for the I²C bus.
Output is open drain type.
ST
Input/output or data input for the SPI, or data for the I²C bus.
Output is open drain type.
ST
Input or USART1 Asynchronous Receive input, or
USART1 Synchronous Data input/output.
ST
Input or USART1 Asynchronous Transmit output, or
USART1 Synchronous Clock input/output.
RBPU
bit7
—
Control bit for PORTB weak pull-ups.
Legend: ST = Schmitt Trigger input
TABLE 10-2: REGISTERS/BITS ASSOCIATED WITH PORTA
Address
Name
Bit 7 Bit 6 Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on
POR,
BOR
MCLR, WDT
10h, Bank 0
PORTA⁽¹⁾ RBPU
—
RA5/
TX1/CK1
RA4/
RX1/DT1
RA3/
SDI/SDA
RA2/
SS/SCL
RA1/T0CKI
RA0/INT
05h, Unbanked T0STA
INTEDG T0SE T0CS T0PS3 T0PS2 T0PS1 T0PS0
—
13h, Bank 0 RCSTA1 SPEN RX9 SREN CREN
—
FERR
OERR
RX9D
15h, Bank 0
TXSTA1
CSRC TX9 TXEN
SYNC
—
—
TRMT
TX9D
Legend: x = unknown, u = unchanged, - = unimplemented, reads as '0'. Shaded cells are not used by PORTA.
Note 1: On any device RESET, these pins are configured as inputs.
0-xx 11xx
0000 000-
0000 -00x
0000 --1x
0-uu 11uu
0000 000-
0000 -00u
0000 --1u
 1998-2013 Microchip Technology Inc.
DS30289C-page 73