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10 years, 5 months ago.
putc and strange situetion
Hi to all i have this strange situation, i want write on serial communication the Hexadecimal number for use the Modbus RTU communication i write this easy code:
#include "mbed.h"
Serial pc(SERIAL_TX, SERIAL_RX);
DigitalOut myled(LED2);
int main() {
while(1) {
myled = !myled;
pc.putc(0xAA); // work well
wait_ms(1000);
}
}
if i run this code all work well, if i use putty for hiperterminal and i see the the two exadecimal AA but if i use
pc.putc(0x03); //or pc.putc(0x03);
i don't see nothing. i don't know where is the problem can you help me? A.
1 Answer
10 years, 5 months ago.
Can you try a different terminal program? 0xAA isn't a standard ascii character so putty displays the hex value. 0x03 is a non-printable but valid ascii character. The correct thing for putty to do is not display it.
Can you try something like Hercules? http://www.hw-group.com/products/hercules/index_en.html
Select the serial tab at the top and then right-click and select Special characters->Hexadecimal. All non-printable characters will now be displayed as hex values in {}'s and hopefully you'll see {03} show up in the output.