Working with interrupts in a CPC system

[lenkoko]

Hello everyone,

We're in the process of designing a system which consists of a Fastwel CPC PC-104 board which runs an MS-DOS operating system, connected to a sensor through the ISA interface.

We read the values from the sensor in an interrupt driven manner and performed some minimal processing on them inside the interrupt handler. This logic is performed inside an IRQ0 interrupt handler that runs at a frequency of a few kilo-hertz.

It seems that at some point, in a random manner, our interrupt code isn't called anymore and thus the logic that deals with receiving the input data from the sensor stops working completely.

We tried inspecting the interrupt code and measuring the time it takes to perform each interrupt handling routine to make sure we're not overloading the system, but it looks reasonable.

Any suggestions?

 

[JacobMR]

Have you tried upgrading your BIOS to the newest version?
Could perhaps be more stable and solve your problem

 

[Romana]

Hiii...
Interrupts are frequently used in modern hardware devices that have a processor and one or more peripheral devices. Interrupts offer a practical method of allocating CPU time among multiple hardware and software activities. Events that happen intermittently but may need to be handled promptly frequently occur in peripheral devices. Instead of waste processor time polling a peripheral device on a regular basis to check if an event that needs handling has happened, a processor can work on other tasks and have the peripheral device send an interrupt request when an event that needs handling happens.
Thus, an interrupt request asynchronously alerts a processor that it needs to perform a processor service. Typically, an interrupt service is a piece of code that goes along with every interrupt.