Dear Sir or Madam, I am using Dsk 5402 board and I want to connect two of them via Uart Rs232 directly without any hardware between the two boards, except by a cable with two db9 connectors in its extremes. Could you answer these doubts? 1.- Where are adressed the Brg and Iir registers? 2.- Which connections among the pins of rs232 port should I do to connect directly both boards?Which C code should I use? 3.- Could you say to me if these are the connections among the pins of the port and signals? \/ \1 2=rxd 3=txd 4=dtr 5=gnd / \ 6=dsr 7=rts 8=cts 9=ci /<-----it is the front view of rs232 port \------------------------------/ I make you this question because I am executing the following code and I observing data in pin 2 with my oscilloscope and they should be observe in pin 3: void emision(void) { const int putchar = 'A'; uart_reset(); uart_init(); uart_setup(UART_BAUD_9600, UART_WORD8, UART_STOP1, UART_DISABLE_PARITY, UART_FIFO_ENABLE, UART_NO_LOOPBACK); while(1) { uart_fputc(putchar); } } 4.- Does the pin rxd is used to recieve data from dsp in order to send to the channel or to recieve data from channel to be read by Dsp? 5.- In relation with the previous code, which is the purpose of the fifo abiliy and the loopback? 6.- Could you send me a program in C code to communicate the two boards. I want to transmit data of 8 or 16 bits. I want a program to know when the transmitter is able to write and the receiver knows when has received data. That is to say, when I want to transmit data from rs232 to the external of the board: 6.1.-which instruction must I use? 6.2- Must I check any flag to know if the transmission of this data has finished? 6.3.-In reception, which flag does my code have to check if it has received the data? 6.4.-With Which intruction can I access to these data? Where can I find more information about Uart? I think any of the manuals I have provide the enough information about Rs232. Please, help me, I have not very much time. Yours faithfully Roberto Espinosa Espeleolectronic Devices, Spain. --------------------------------- Yahoo! Messenger Nueva versi: Super Webcam, voz, caritas animadas, y m #161;Gratis! |
uart doubts
Started by ●November 8, 2003