Hello, I need help with the serial communication, when I am sending data from PC (hyper-terminal) through RS232 , RI flag should rise to '1' and its does not happened, what may be the problem?
BTW, when I am programming the same device in the PLCC package the flag is triggered, I am currently use the VQFP package witch I have problem with.
Note that the pinouts of different packages are not necessarily the same...
Also, you haven't said what chip you're using!
Are you sure that valid data is actually reaching the UART's input pin?
I am using AT89C5130A uC.. I know that the pinout may be different , my pcb pinout schematic fine. when I am sending the data to the PC its work well. I am using the same oscillator (16MHz freq.). maybe I also need to check TI flag ?? again sending from the uC to the PC works well!
thanks for your help!
So, you checked off two of my items - same crystal frequency and correct baudrate to be able to send to the PC.
What about the other items I listed?
Knowing that the two packages have different pinouts isn't the same as having verified that the serial data signal is reaching the correct pin on the processor, and with correct voltage levels and timing. Have you used an oscilloscope and checked?
Yes I verified the connection on the processor. checked with oscilloscope voltage level seems fine 5V..
But, if the serial data is arriving at that pin, you would not just see a 5V voltage, would you?
What, exactly, do you see? Is it valid serial data?
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