:::
Browsing this Thread:
1 Anonymous Users
|
Re: PIC18F4520的RS232輸出奇怪的現象求教?
|
||||
|---|---|---|---|---|
|
資深會員
 
|
每次都是第一次異常,之後就正確嗎????
有可能是第一次的接收被干擾到了,可以加一點安全機制. 例如: 0x5A + data1 + data2 +.... +dataN + CheckSum 0x5A 做同步用,CheckSum確定資料正確. CheckSum= 0x5A + data1 + data2 +.... +dataN
發表於: 2009/7/15 11:39
|
|||
|
||||
|
PIC18F4520的RS232輸出奇怪的現象求教?
|
||||
|---|---|---|---|---|
|
資深會員
|
程式碼如下:
#include <p18f4520.h> #include <usart.h> unsigned char Tx_Data_Buf0=0xAA; unsigned char Tx_Data_Buf1=0xBB; unsigned char Tx_Data_Buf2=0xCC; unsigned char Tx_Data_Buf3=0xDD; void main(void) { OpenUSART( USART_TX_INT_OFF & USART_RX_INT_OFF & USART_ASYNCH_MODE & USART_EIGHT_BIT & USART_CONT_RX & USART_BRGH_HIGH,15 ); //4xPLL, 外頻7.37MHz while(1){ while(!TXSTAbits.TRMT); TXREG=Tx_Data_Buf0; while(!TXSTAbits.TRMT); TXREG=Tx_Data_Buf1; while(!TXSTAbits.TRMT); TXREG=Tx_Data_Buf2; while(!TXSTAbits.TRMT); TXREG=Tx_Data_Buf3; Nop(); } } 結果執行第一次迴圈終端機接收的資料為 00 BB CC DD 執行第二次迴圈終端機接收的資料為 AA BB CC DD 請問上述程式哪裡出錯,為何一開始輸出不是AA
發表於: 2009/7/14 22:44
|
|||
|
||||
You can view topic.
你 不可以 發起新主題
You cannot reply to posts.
You cannot edit your posts.
You cannot delete your posts.
You cannot add new polls.
You cannot vote in polls.
You cannot attach files to posts.
You cannot post without approval.
You cannot use topic type.
You cannot use HTML syntax.
You cannot use signature.
You cannot create PDF files.
You cannot get print page.
