PIC16C74-04/P Microchip Technology, PIC16C74-04/P Datasheet - Page 107

• Manufacturer Part Number: PIC16C74-04/P
• Description: MICRO CTRL 4K 4MHZ OTP 40DIP
• Manufacturer: Microchip Technology
• Series: PIC® 16Cr

Specifications of PIC16C74-04/P

• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 4MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: POR, PWM, WDT
• Number Of I /o: 33
• Program Memory Size: 7KB (4K x 14)
• Program Memory Type: OTP
• Ram Size: 192 x 8
• Voltage - Supply (vcc/vdd): 4 V ~ 6 V
• Data Converters: A/D 8x8b
• Oscillator Type: External
• Operating Temperature: 0°C ~ 70°C
• Package / Case: 40-DIP (0.600", 15.24mm)
• Lead Free Status / RoHS Status: Request inventory verification / Request inventory verification
• Eeprom Size: -

Steps to follow when setting up an Asynchronous
Transmission:
1.
2.
3.
FIGURE 12-8: ASYNCHRONOUS MASTER TRANSMISSION
FIGURE 12-9: ASYNCHRONOUS MASTER TRANSMISSION (BACK TO BACK)
TABLE 12-6:
Address Name
0Ch
18h
19h
8Ch
98h
99h
Legend: x = unknown, - = unimplemented locations read as '0'. Shaded cells are not used for Asynchronous Transmission.
Note 1: Bits PSPIE and PSPIF are reserved on the PIC16C73/73A/76, always maintain these bits clear.
1997 Microchip Technology Inc.
TXIF bit
(interrupt reg. flag)
RC6/TX/CK (pin)
RC6/TX/CK (pin)
Initialize the SPBRG register for the appropriate
baud rate. If a high speed baud rate is desired,
set bit BRGH. (Section 12.1)
Enable the asynchronous serial port by clearing
bit SYNC and setting bit SPEN.
If interrupts are desired, then set enable bit
TXIE.
TRMT bit
(Transmit shift
reg. empty flag)
Write to TXREG
Write to TXREG
TXIF bit
(Transmit buffer
reg. empty flag)
TRMT bit
(Transmit shift
reg. empty flag)
BRG output
(shift clock)
BRG output
(shift clock)
PIR1
RCSTA
TXREG USART Transmit Register
PIE1
TXSTA
SPBRG Baud Rate Generator Register
REGISTERS ASSOCIATED WITH ASYNCHRONOUS TRANSMISSION
Note: This timing diagram shows two consecutive transmissions.
PSPIF
PSPIE
CSRC
SPEN
Bit 7
Transmit Shift Reg.
WORD 1
WORD 1
Transmit Shift Reg
(1)
(1)
Word 1
Word 1
ADIF
ADIE
Bit 6
RX9
TX9
Start Bit
Start Bit
Word 2
SREN
TXEN
RCIF
RCIE
Bit 5
CREN
SYNC
Bit 0
Bit 4
TXIF
TXIE
Bit 0
SSPIF CCP1IF
SSPIE CCP1IE TMR2IE TMR1IE
Bit 3
—
—
Bit 1
WORD 1
Bit 1
4.
5.
6.
7.
WORD 1
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 trans-
mission).
TMR2IF
OERR
TRMT
Bit 1
Bit 7/8
WORD 2
Transmit Shift Reg.
TMR1IF
Bit 7/8
RX9D
TX9D
Bit 0
Stop Bit
PIC16C7X
Stop Bit
0000 0000
0000 -00x
0000 0000
0000 0000
0000 -010
0000 0000
Value on:
POR,
BOR
Start Bit
DS30390E-page 107
WORD 2
0000 0000
0000 -00x
0000 0000
0000 0000
0000 -010
0000 0000
Value on
all other
Resets
Bit 0