> Hi,
> Quick question. Is it possible to selectively disable interrupts for a given
> IRQ in 386 architecture or can one only disable all interrupts. We are
> working on a device driver for a rather stupid device. As we are waiting for
> a register to clear on the device, it appears the device is interrupting and a
> new device command from the interrupt routine is reseting the register.
> Unfortunately disabling interrupts on the device also clears the register.
> Any suggestions?
>
> Bob Welsh
>
Shure can. The control port for the "low" IRQs is at 0x21 and the
"high" IRQs is at 0xA1. It is a bit-mapped mask, bit 0 is IRQ0 on
the low port. Bit 0 is IRQ8 on the high port (the interrupt controllers
are cascaded).. These ports are R/W, you can save the bits then put
them back the way they were.
Cheers,
Dick Johnson
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Richard B. Johnson
Project Engineer
Analogic Corporation
Voice : (508) 977-3000 ext. 3754
Fax : (508) 532-6097
Modem : (508) 977-6870
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