8-bit Microcontrollers中的主题 Re: Trigger A, B & C Occured error message

Trigger A, B & C Occured error message - DEMOQE

Rodo55 — Mon, 30 Jun 2008 14:39:25 GMT

Hello,

I'm using a DEMOQE board with a QE8 MCU, Running CW 6.1 .

I'm receiving an error message Trigger A, B & C occurred when I run an RTC ISR program. It occurs after 103 loops through what should be an endless loop. Just before that the error message says the Freq. Changed to 0Hz. I suspect a memory over run but I don't see in my code where that is happening. Does anyone have any suggestions as to what and maybe where to look?

I have not set any triggers in the debugger either.

I attached a file with the code in case someone can see where I went wrong.

The error message is at the bottom of the file.

Thanks,

Rodo

Added p/n to subject

Message Edited by NLFSJ on 2008-06-30 02:29 PM

Re: Trigger A, B & C Occured error message

peg — Mon, 30 Jun 2008 15:02:07 GMT

Hello Rodo,

After a very quick look I can see two issues:

1: STATE_3 can fall through into the RTI ISR, probably not intended.

2: You are jumping out of an ISR without a RTI this will not de-stack the stuff stacked on interrupt entry.

Stack Overflow!

Re: Trigger A, B & C Occured error message

Rodo55 — Mon, 30 Jun 2008 18:40:25 GMT

Thanks Peg,

There's more code than what I included, so that's why it looks like it could fall through from State_3.

As far as the RTI, I originally wrote it that way but the program gets caught in a loop where it switches back and forth between the NOP and the RTI. It never returns from the ISR. When I stop the program and do an assembly step it's always stuck between the RTI and NOP. It didn't make any sense to me so I put the JMP there to get it to State_1.

Any thoughts as to why it wouldn't return with the RTI?

Rodo

Re: Trigger A, B & C Occured error message

peg — Mon, 30 Jun 2008 18:55:49 GMT

Hi Rodo,

That's because additionally you are not clearing the source of the interrupt.
Something like BSET RTIF,RTCSC at the start of the ISR should do the trick.

Re: Trigger A, B & C Occured error message

bigmac — Mon, 30 Jun 2008 18:56:33 GMT

Hello Rodo,

Unless the interrupt flag for the RTC is cleared, the ISR will be continuously re-entered.

Regards,

Mac

Re: Trigger A, B & C Occured error message

Rodo55 — Mon, 30 Jun 2008 19:07:24 GMT

Hi Peg,

I am a beginner at this so I made a beginners mistake.

It never came out of the ISR because I didn't clear the RTC Interrupt flag. I cleared the flag and now it returns.

Thanks for your help.

Rodo

Re: Trigger A, B & C Occured error message

Rodo55 — Mon, 30 Jun 2008 19:31:02 GMT

Thanks Again Peg and Mac.

A beginner mistake from a beginner.

I have a follow-up question about the BSET RTIF,RTCSC.

Since RTCSC is a high address ($1830) when I use that command I get the error: A13003: Value is truncated to one byte.

I figured that was normal since it's a high address?

I used this instead so I don't get an error:

LDA RTCSC

ORA #%10000000

STA RTCSC

It seems to work fine but I was wondering if the error I got is a real error or is there an option or definition I need to set?

Re: Trigger A, B & C Occured error message

peg — Mon, 30 Jun 2008 19:37:35 GMT

Hi Rodo,

Yes, this is what you need to do.
BSET only works within page zero (address 00 to FF)
I am not familiar with this device and the manual does not give you the address within the relevant section, so I lead you astray here, sorry.
At least you now have learnt something else.

Re: Trigger A, B & C Occured error message

Rodo55 — Mon, 30 Jun 2008 19:48:00 GMT

Hi Peg,

No, you didn't lead me astray, you set me straight and got me running again. Thanks!

I asked the question because the smart people like yourself sometimes have tricks of the trade they know that can help beginners like me. I was thinking you may have known about an option or macro that would make that command work with higher addresses.

Thanks Again,

Rodo