8259 Guru wanted

8259 Guru wanted

Post by Juergen Marquard » Thu, 13 Jan 2000 04:00:00



Hi all,
I'm seraching for a 8259 (ex Intel Peripheral Interrupt Controller) guru.

Unfortunately Intel doesnt support this chip anymore and they removed
all application notes from their web sites.

The published data sheet is somewhat unclear in what the chip does,
especially
when using it in polling mode (e.g. when the INT output is reset).

So if anyone has the application notes or links to them or know how to
solve our problems with the chip DON HESITATE to mail to

Sincerely,
Juergen Marquardt

 
 
 

8259 Guru wanted

Post by James T. Whit » Sat, 15 Jan 2000 04:00:00


Check out Intersil's Website at www.intersil.com.  Then search for 82C59.
They have a 14 page Application Note for the 82C59A.  Enjoy.


> Hi all,
> I'm seraching for a 8259 (ex Intel Peripheral Interrupt Controller) guru.

> Unfortunately Intel doesnt support this chip anymore and they removed
> all application notes from their web sites.

> The published data sheet is somewhat unclear in what the chip does,
> especially
> when using it in polling mode (e.g. when the INT output is reset).

> So if anyone has the application notes or links to them or know how to
> solve our problems with the chip DON HESITATE to mail to

> Sincerely,
> Juergen Marquardt


 
 
 

8259 Guru wanted

Post by Steve Hol » Tue, 18 Jan 2000 04:00:00


I believe Harris is still supporting this device.
On Fri, 14 Jan 2000 23:28:34 -0600, "James T. White"

>Check out Intersil's Website at www.intersil.com.  Then search for 82C59.
>They have a 14 page Application Note for the 82C59A.  Enjoy.



>> Hi all,
>> I'm seraching for a 8259 (ex Intel Peripheral Interrupt Controller) guru.

>> Unfortunately Intel doesnt support this chip anymore and they removed
>> all application notes from their web sites.

>> The published data sheet is somewhat unclear in what the chip does,
>> especially
>> when using it in polling mode (e.g. when the INT output is reset).

>> So if anyone has the application notes or links to them or know how to
>> solve our problems with the chip DON HESITATE to mail to

>> Sincerely,
>> Juergen Marquardt

 
 
 

1. Two 8259 problems for the gurus clarified

Hi,

meanwhile I got some test software running and observed
the INT output and the CS input with a scope.
I got the following result when issuing the poll command and the
read access (best viewed in COURIER or FIXED font):

        ____________________    _____
INT                         |__|     |_________________
        ___________________    ___    _________________
/CS                        |__|   |__|
                            ^      ^
                            |      |
                            |      Read access
                            Poll command

It is seen, that the poll command releases the INT output for a short
time, rises it again, and the following read command finishes the
acknowledge cycle with releasing the INT output fully.

Does anyone knows an application note or FAE material which addresses
this behaviour?

Another problem is discussed: Someone says the 8259 is not resettable by
software, e.g. one cannot clear the IRR bits with a software command.
If the 8259 was programmed to react on an edge (LTIM=0) and got an edge
it will set the corresponding IRR bit.
They say one can get rid of this IRR bit only with executing the interrupt
acknowledge cycle (/INTA pulse or Poll command) which would set the ISR bit
and clear the IRR bit.

Thes are the two main problems I try to solve with clarification by an
experienced fellow.

Regards
Juergen

2. \caption Q: how to produce shorter .lof and .lot

3. Question on 8259 PICs, Interrupts, ISR

4. Enthusiasts in Surrey and Sussex

5. Slave 8259 PIC initialized problem, on memtest86 v3.0??

6. Works in all Ver. of Windows except Win2k

7. 8259 application information STILL NEEDED!

8. Help OS/2

9. 8259 compatable processors

10. 8259 Extended Mode Register

11. programming UART 8259

12. Interface 8051 to 8259 ???

13. Is the 8085 compatible with the 8259 int. controller?