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copied!<p>Consider the following method to send 2 variable at the same time:</p> <pre><code> int xpos, ypos; char x_tx_buffer[20], y_tx_buffer[20]; char x_dummy_buffer[20]; char y_dummy_buffer[20]; char *p_x_tx_buffer, *p_y_tx_buffer; sprintf(x_dummy_buffer,"%d", xposs); sprintf(y_dummy_buffer,"%d", yposs); p_x_tx_buffer = &x_tx_buffer[0]; *p_x_tx_buffer++ = x_dummy_buffer[0]; *p_x_tx_buffer++ = x_dummy_buffer[1]; *p_x_tx_buffer++ = x_dummy_buffer[2]; *p_x_tx_buffer++ = x_dummy_buffer[3]; p_y_tx_buffer = &y_tx_buffer[0]; *p_y_tx_buffer++ = y_dummy_buffer[0]; *p_y_tx_buffer++ = y_dummy_buffer[1]; *p_y_tx_buffer++ = y_dummy_buffer[2]; *p_y_tx_buffer++ = y_dummy_buffer[3]; uart0_filestream = open("/dev/ttyAMA0", O_RDWR | O_NOCTTY | O_NDELAY); //Open in non blocking read/write mode if (uart0_filestream == -1) { //ERROR - CAN'T OPEN SERIAL PORT printf("Error - Unable to open UART. Ensure it is not in use by another application\n"); } if (uart0_filestream != -1) { int countx = write(uart0_filestream, &x_tx_buffer[0], (p_x_tx_buffer - &x_tx_buffer[0])); //Filestream, bytes to write, number of bytes to write int county = write(uart0_filestream, &y_tx_buffer[0], (p_y_tx_buffer - &y_tx_buffer[0])); //Filestream, bytes to write, number of bytes to write if (countx < 0 || county < 0) { printf("UART TX error\n"); } } close(uart0_filestream); </code></pre> <p>You can send a max of 8 bytes at a time. Keep that in mind and with that you can modify the about code to send your x and y values in the same uart0_filestream.</p> <p>Good luck.</p>

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