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OPERATIONS MANUAL PCM-UIO48B
10
CLR_INT
– Clears the specified pending interrupt
Syntax
void clr_int(int bit_number);
Description
This function takes a single argument:
bit_number – a value from 1 to 24 specifying the bit
number to reset the interrupt.
This function clears a pending interrupt on the
specified bit. It does this by disabling and reenabling
the interrupt. The net result after the call is that
the interrupt is no longer pending and is renamed
for the next transition of the same polarity. Calling
this function on a bit that has not been enabled for
interrupts will result in its interrupt being enabled with
an undefined polarity. Calling this function with no
interrupt pending will have no adverse effect. Only the
specified bit is affected.
GET_INT
– Retrieves bit number of pending interrupt
Syntax
void get_int(void);
Description
This function requires no arguments.
This function returns either a
0
for no bit interrupts
pending or a value between 1 and 24 representing a
bit number that has a pending edge detect interrupt.
The function returns with the first interrupt found
and begins its search at Port 0 bit 0 proceeding
through to Port 2 Bit 7. It is necessary to use either
clr_int() or disab_int() to avoid returning the same
bit continuously. This function may be used in an
application’s ISE or can be used in the foreground to
poll for bit transitions.