keep IRQ fire count high so that after switching off IRQ mode the busy wait loop still sees IRQs occured.
keep IRQ fire count high so that after switching off IRQ mode the busy
wait loop still sees IRQs occured.

joncampbell123/doslib,joncampbell123/doslib,joncampbell123/doslib,joncampbell123/doslib,joncampbell123/doslib,joncampbell123/doslib