Controlling a PIC through SERIAL PORT

pic serial received interrupt

Hi guys!

hope u would be fine out there!

well! im trying to control a motor through PIC and the PIC will be commanded by my PC through serial port.

Now what actually i want here to do is to dedicate two pins of serial i.e. TXD and RXD with my PIC16F876 pins RXD and TXD respectively. I want another pin from the serial port, which can be used as an INTERRUPT pin on my PIC External Interrupt Pin.

Here is what im trying to do!

supposing my PIC is running the motor in the forward direction, i send a 4 bit code from my PC through serial port, but before sending it, it first INTERRUPT the PIC externally so that PIC can know that a new 4-bit code is coming and then the 4-bit code should be sent through TXD of Serial port.

Is this possible?

what port of SERIAL CABLE can i use to generate this INTERRUPT command??

Which will be the difference if you'll send an ASCII command directly to the PIC serial port, telling your motor to stop and reverse ?
Of course every step or group of steps movement must be programmed either.

If you need intterupts from COM port, the output signals available are DTR or RTS.

Is there a reason that you couldn't use a USART receive interrupt or timed interrupt to poll the buffer on the PIC?

I agree with both melc and ldanielrosa.

But if you still want your solution... service Interrupt 0.