WinSystems EBC-LP, Руководство по эксплуатации

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CLR_INT - Clear the speci fied pend ing in ter rupt
Syn tax
void clr_int(int bit_number);
De scrip tion
This func tion re quires a sin gle ar gu ment:
bit_number - The speci fied bit number from 1 to 24 to re set the in ter rupt.
This func tion clears a pend ing in ter rupt on the speci fied bit. It does this by dis abling and reena bling
the in ter rupt. The net re sult af ter the call is that the in ter rupt is no longer pend ing and is re armed for the
next tran si tion of the same po lar ity. Call ing this func tion on a bit that has not been en abled for in ter rupts
will re sult in its in ter rupt be ing en abled with an un de fined po lar ity. Call ing this func tion with no
in ter rupt pend ing will have no ad verse af fect. Only the speci fied bit is af fected.
GET_INT - Re trieve bit number of pend ing in ter rupt
Syn tax
int get_int(void);
De scrip tion
This func tion re quires no ar gu ments and re turns ei ther a '0' for no bit in ter rupts pend ing or a value
be tween 1 and 24 rep re sent ing a bit number that has a pend ing edge de tect in ter rupt. The func tion
re turns with the first in ter rupt found and be gins its search at Port 0 Bit 0 pro ceed ing through to Port 2 Bit
7. It is nec es sary to use ei ther clr_int() or disab_int() to avoid re turn ing the same bit con tinu ously. This
func tion may ei ther be used in an ap pli ca tion's ISR or can be used in the fore ground to poll for bit
tran si tions.
030530 EBC-LP OPERATIONS MANUAL Page 5-5
WinSystems - "The Embedded Authority"