Consider the following interrupting system. The active-edge inputs on PJ7 and PP7 can occur at any time, including at the same time. The object is to count the number of each type of interrupt.
How would you best describe the usage of Count in this system?
a) This is a perfectly appropriate usage of Count, because there are two permanently allocated variables with private scope, such that each variable counts the number of interrupts for each ISR.
b) There is a critical section bug because of the read/modify/write access to a shared global.
c) Because both ISRs share the same Count, the system can not distinguish between a PJ7 and a PP7 interrupt.
d) Count is initialized each interrupt, so its value is not the total number.
e) The acknowledge statements in the two ISRs are not friendly because they affect all 8 bits of the flag register.
f) None of the above is true.