Microchip Technology DV164139 データシート

DS41356B-page 35

EXAMPLE 2-10:

INITIALIZEUSART() CODE

The reader is encouraged to review the data sheet for the PIC18F14K50 EUSART
section for more information on the specifics of the configuration code.

Next, the application specific code will be added that will implement the flowchart
shown in Figure 2-6.

10. Scroll down to the ProcessIO()and copy and paste the contents of

Example 2-11 into the section labeled:

/*****************************************************

ADD CODE TO CHECK IF RS232 HAS

BEEN SENT ALONG USB

AND THE CODE TO CHECK IF

ANY NEW RS232 TRANSMISSION

HAS BEEN RECEIVED AND STORED

******************************************************/

As per the flowchart in Figure 2-6, this code will ensure that the buffer containing the
data transmitted from the RS-232 has been sent to the USB firmware. If so, the code
then checks for any new RS-232 data that has been stored in the buffer.

#if defined(__18CXX)

unsigned char c;

#if defined(__18F14K50)

ANSELHbits.ANS11 = 0;

// Make RB5 digital so USART can

//use pin for Rx

#endif

UART_TRISRx=1;

// RX

UART_TRISTx=0;

// TX

TXSTA = 0x24;

// TX enable BRGH=1

RCSTA = 0x90;

// Single Character RX

SPBRG = 0x70;

SPBRGH = 0x02;

// 0x0271 for 48MHz -> 19200 baud

BAUDCON = 0x08;

// BRG16 = 1

c = RCREG;

// read

#endif