Embedded programming interrupts a problem

Interrupts is an important part of embedded systems. Consequently, many compiler vendors offer an extension

To standard C-to-support interrupts. Typically, the keyword is _interrupt. The following routine (ISR), point out

The errors in the code.

double Compute_area (double  radius) {    double area = PI * radius * radius;    printf ("\narea =%f", area);     return 0 ;}

Analysis

1) ISR cannot return a value
2) ISR cannot pass parameters
3) In many processors or compilers, floating point is generally non-reentrant, in addition, the ISR should be short and efficient, it is unwise to do floating point in the ISR
4) printf () often has re-entry and performance problems, so it is generally not used with printf ()

Embedded programming interrupts a problem