FX2 interrupt mixed?

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Hi everybody

I have a strange problem with a cypress FX2. I want to work with timers
and external events on INT0 and INT1 Pin. (I want to measure the time
beween an event on INT0 and INT1).
 Everything works fine except I get the interrupts IE0, TF0, IE1 and TF1
alltogether on interrupt vector 0x1b (normally only TF1).

If I use 'interrupt 3' everthing works fine. I can enable/disable Timer0
and/or Timer1 and I get the expected result but only on interrupt 3.
The same with INT0 and INT1. I get the events but on interrupt 3.

What's wrong?

When I check main.lst everything seems to be ok:
   0000                     630 __interrupt_vect:
   0000 02s00r00            631     ljmp    __sdcc_gsinit_startup
   0003 32                  632     reti
   0004                     633     .ds    7
   000B 32                  634     reti
   000C                     635     .ds    7
   0013 32                  636     reti
   0014                     637     .ds    7
   001B 02s01r53            638     ljmp    _isr01
   001E                     639     .ds    5
   0023 32                  640     reti
   0024                     641     .ds    7
   002B 32                  642     reti
   002C                     643     .ds    7
   0033 32                  644     reti
   0034                     645     .ds    7
   003B 32                  646     reti
   003C                     647     .ds    7
   0043 02s00r00            648     ljmp    _autovector_jump_table_usb
   0046                     649     .ds    5
   004B 32                  650     reti
   004C                     651     .ds    7
   0053 02s00r00            652     ljmp    _autovector_jump_table_gpif

How can I get Interrupts on other vectors than 0x1B. Or is it a hardware
The autovector interrupts work fine.

BTW I use sdcc 2.4.

I hope someone can give me some hints.

Michael Bahrs

Re: FX2 interrupt mixed?
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<table snipped>

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Thats very interesting, I'm currently working with EZUSB FX (not 2) and
I'm having great trouble trying to get #INT0 working.  I'm using it in
level sensitive mode, and I can see IE0 in the TCON register changing
state when I change the pin state, and my interrupt mask is correct, but
the service routine never gets called.  Whats even stranger is that
sometimes the value of IE gets changed at this point, such that other
interrupts, like the timer, which were previously working stop
functioning.  I've also seen the PC go off into space at this point as

I'm also using SDCC, and as far as I can tell, the code its generating
is correct - there is an ljmp at the vector (0x0003) which points to my
service routine.  I've done all this before on the standard EZUSB
(AN2131) and its worked perfectly.

I've not really had much help from Cypress so far, who keep suggesting
that I'm not using the 'keil' compiler correctly!

There is also a post on their support site that suggests that other
people have seen a similar bug - Article 16525, but it has no fix or



Re: FX2 interrupt mixed?

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I've seen this behavior with 8051's when an ISR is returned from via a ret
or jmp instead of an iret. I discovered this trying to "reset" my CPU by
jumping to 0x0000 from an external interrupt ISR. Problem was, after that,
no more interrupts get serviced. Try and see if there is any way that you
might be exiting an ISR without an iret.

- Mark ->

Re: FX2 interrupt mixed?

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  Sometimes a debug system can fight for interrupt resource?

  The 80C51 has 8 bytes for each INT vector, so a simple way to verify
INT vector entry, is to allocate a FLAG byte, and code to set that
on the first opcode. ( or it can even be a port pin )
  Later debug-break can safely inspect that collection of flags, to see
what occured.

  Start with the simplest code, and work upwards.

ORG     0003H
      SETB BitTrackVariable.0      ; Catch expected vector
    LJMP Vector0003Name
ORG     000BH
      SETB BitTrackVariable.1   ; Catch/flag an unexpected vector
.. etc for ALL vectors.

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