PIC16F946T-I/PT Microchip Technology, PIC16F946T-I/PT Datasheet - Page 148

• Manufacturer Part Number: PIC16F946T-I/PT
• Description: Microcontroller
• Manufacturer: Microchip Technology
• Series: PIC® 16Fr

Specifications of PIC16F946T-I/PT

• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 20MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, LCD, POR, PWM, WDT
• Number Of I /o: 53
• Program Memory Size: 14KB (8K x 14)
• Program Memory Type: FLASH
• Eeprom Size: 256 x 8
• Ram Size: 336 x 8
• Voltage - Supply (vcc/vdd): 2 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 64-TFQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: MA160011 - DAUGHTER BOARD PICDEM LCD 16F91X
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant

PIC16F946
11.3.2
Once Synchronous mode is selected, reception is
enabled
(RCSTA<5>), or enable bit, CREN (RCSTA<4>). Data
is sampled on the RC7/RX/DT/SDI/SDA/SEG8 pin on
the falling edge of the clock. If enable bit SREN is set,
then only a single word is received. If enable bit CREN
is set, the reception is continuous until CREN is
cleared. If both bits are set, CREN takes precedence.
After clocking the last bit, the received data in the
Receive Shift Register (RSR) is transferred to the
RCREG register (if it is empty). When the transfer is
complete, interrupt flag bit, RCIF (PIR1<5>), is set. The
actual interrupt can be enabled/disabled by set-
ting/clearing enable bit, RCIE (PIE1<5>). Flag bit RCIF
is a read-only bit which is reset by the hardware. In this
case, it is reset when the RCREG register has been
read and is empty. The RCREG is a double-buffered
register (i.e., it is a two-deep FIFO). It is possible for two
bytes of data to be received and transferred to the
RCREG FIFO and a third byte to begin shifting into the
RSR register. On the clocking of the last bit of the third
byte, if the RCREG register is still full, then Overrun
Error bit, OERR (RCSTA<1>), is set. The word in the
RSR will be lost. The RCREG register can be read
twice to retrieve the two bytes in the FIFO. Bit OERR
has to be cleared in software (by clearing bit CREN). If
bit OERR is set, transfers from the RSR to the RCREG
are inhibited so it is essential to clear bit OERR if it is
set. The ninth receive bit is buffered the same way as
the receive data. Reading the RCREG register will load
bit RX9D with a new value, therefore, it is essential for
the user to read the RCSTA register before reading
RCREG in order not to lose the old RX9D information.
TABLE 11-9:
DS41265A-page 146
0Bh, 8Bh,
10Bh,18Bh
0Ch
18h
1Ah
8Ch
98h
99h
Legend:
Address
by
x = unknown, – = unimplemented, read as ‘0’. Shaded cells are not used for synchronous master reception.
USART SYNCHRONOUS MASTER
RECEPTION
INTCON
PIR1
RCSTA
RCREG
PIE1
SPBRG
TXSTA
Name
setting
REGISTERS ASSOCIATED WITH SYNCHRONOUS MASTER RECEPTION
USART Receive Data Register
Baud Rate Generator Register
CSRC
SPEN
EEIF
EEIE
Bit 7
GIE
either
ADIF
ADIE
Bit 6
PEIE
RX9
TX9
enable
SREN
TXEN
RCIF
RCIE
Bit 5
T0IE
bit,
SREN
CREN ADDEN
SYNC
INTE
TXIF
TXIE
Bit 4
Preliminary
SSPIF
SSPIE
RBIE
Bit 3
—
When setting up a Synchronous Master Reception:
1.
2.
3.
4.
5.
6.
7.
8.
9.
10. If any error occurred, clear the error by clearing
11. If using interrupts, ensure that GIE and PEIE
CCP1IF TMR2IF TMR1IF 0000 0000 0000 0000
CCP1IE TMR2IE TMR1IE 0000 0000 0000 0000
BRGH
FERR
Bit 2
T0IF
Initialize the SPBRG register for the appropriate
baud rate (Section 11.1 “USART Baud Rate
Generator (BRG)”).
Enable the synchronous master serial port by
setting bits SYNC, SPEN and CSRC.
Ensure bits CREN and SREN are clear.
If interrupts are desired, then set enable bit
RCIE.
If 9-bit reception is desired, then set bit RX9.
If a single reception is required, set bit SREN.
For continuous reception, set bit CREN.
Interrupt flag bit RCIF will be set when reception
is complete and an interrupt will be generated if
enable bit RCIE was set.
Read the RCSTA register to get the ninth bit (if
enabled) and determine if any error occurred
during reception.
Read the 8-bit received data by reading the
RCREG register.
bit CREN.
(bits 7 and 6) of the INTCON register are set.
OERR
TRMT
Bit 1
INTF
RX9D
TX9D
RBIF
Bit 0
© 2005 Microchip Technology Inc.
0000 000x 0000 000x
0000 000x 0000 000x
0000 0000 0000 0000
0000 -010 0000 -010
0000 0000 0000 0000
POR, BOR
Value on:
Value on
all other
Resets