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VdGetFreeWd

int VdGetFreeWd( char count );

Description

Returns a free virtual watchdog and initializes that watchdog so that the virtual driver begins counting it down from count. The number of available virtual watchdogs is determined by the macro N_WATCHDOG, which is 10 by default. The default can be overridden by the user, e.g., #define N_WATCHDOG 11.

The virtual driver is called every 0.00048828125 second. On every 128th call to it (i.e., every 62.5 ms), the virtual watchdogs are counted down and then tested. If any virtual watchdog reaches zero, this is a fatal error. Once a virtual watchdog is active, it should reset periodically with a call to VdHitWd() to prevent the count from readching zero.

Parameters

count

1 < count <= 255

Return value

Integer id number of an unused virtual watchdog timer.

Library

VDRIVER.LIB