PIC16F88-I/SO Microchip Technology Inc., PIC16F88-I/SO Datasheet - Page 105

• Manufacturer Part Number: PIC16F88-I/SO
• Description: 18 PIN, 7 KB FLASH, 368 RAM, 16 I/O
• Manufacturer: Microchip Technology Inc.

Specifications of PIC16F88-I/SO

• A/d Inputs: 7-Channel, 10-Bit
• Comparators: 2
• Cpu Speed: 5 MIPS
• Eeprom Memory: 256 Bytes
• Input Output: 16
• Interface: I2C/SPI/USART
• Memory Type: Flash
• Number Of Bits: 8
• Package Type: 18-pin SOIC
• Programmable Memory: 7K Bytes
• Ram Size: 368 Bytes
• Speed: 20 MHz
• Timers: 2-8-bit, 1-16-bit
• Voltage, Range: 2-5.5 V
• Lead Free Status / Rohs Status: RoHS Compliant part Electrostatic Device

When setting up an asynchronous transmission, follow
these steps:
1.
2.
3.
FIGURE 11-2:
FIGURE 11-3:
TABLE 11-7:
 2005 Microchip Technology Inc.
0Bh, 8Bh,
10Bh,18Bh
0Ch
18h
19h
8Ch
98h
99h
Legend:
Note 1:
Address
Write to TXREG
BRG Output
(Shift Clock)
RB5/SS/TX/CK pin
TXIF bit
(Interrupt Reg. Flag)
TRMT bit
(Transmit Shift
Reg. Empty Flag)
Note:
Write to TXREG
BRG Output
(Shift Clock)
RB5/SS/TX/CK pin
(Transmit Buffer
Reg. Empty Flag)
TRMT bit
(Transmit Shift
Reg. Empty Flag)
TXIF bit
Initialize the SPBRG register for the appropriate
baud rate. If a high-speed baud rate is desired,
set bit BRGH (Section 11.1 “AUSART Baud
Rate Generator (BRG)”).
Enable the asynchronous serial port by clearing
bit SYNC and setting bit SPEN.
If interrupts are desired, then set enable bit
TXIE.
This timing diagram shows two consecutive transmissions.
x = unknown, - = unimplemented locations read as ‘0’. Shaded cells are not used for asynchronous transmission.
This bit is only implemented on the PIC16F88. The bit will read ‘0’ on the PIC16F87.
INTCON
PIR1
RCSTA
TXREG AUSART Transmit Data Register
PIE1
TXSTA
SPBRG Baud Rate Generator Register
Name
REGISTERS ASSOCIATED WITH ASYNCHRONOUS TRANSMISSION
CSRC
SPEN
ASYNCHRONOUS MASTER TRANSMISSION
ASYNCHRONOUS MASTER TRANSMISSION (BACK TO BACK)
Bit 7
GIE
—
—
Word 1
Transmit Shift Reg.
Word 1
Transmit Shift Reg
Word 1
Word 1
ADIF
ADIE
Bit 6
PEIE
RX9
TX9
Start Bit
Start Bit
(1)
(1)
Word 2
TMR0IE INT0IE
SREN
TXEN
RCIF
RCIE
Bit 5
Bit 0
CREN ADDEN
SYNC
Bit 4
TXIF
TXIE
Bit 0
SSPIF
SSPIE
RBIE
Bit 3
Bit 1
—
Word 1
Bit 1
Word 1
4.
5.
6.
7.
8.
TMR0IF
CCP1IE TMR2IE
CCP1IF
BRGH
FERR
Bit 2
If 9-bit transmission is desired, then set transmit
bit TX9.
Enable the transmission by setting bit TXEN
which will also set bit TXIF.
If 9-bit transmission is selected, the ninth bit
should be loaded in bit TX9D.
Load data to the TXREG register (starts
transmission).
If using interrupts, ensure that GIE and PEIE
(bits 7 and 6) of the INTCON register are set.
TMR2IF
INT0IF
OERR
TRMT
Bit 1
Bit 7/8
Word 2
Transmit Shift Reg.
Bit 7/8
TMR1IF
TMR1IE
RX9D
TX9D
RBIF
Bit 0
PIC16F87/88
Stop Bit
Stop Bit
0000 000x
-000 0000
0000 000x
0000 0000
-000 0000
0000 -010
0000 0000
POR, BOR
Value on:
Start Bit
DS30487C-page 103
Word 2
0000 000u
-000 0000
0000 000x
0000 0000
-000 0000
0000 -010
0000 0000
Value on
all other
Resets
Bit 0