Now the only interrupt I'm using is the high USART receive, I was =

considering adding USART transmit, though most of the examples leave =

that at polled. The ADC conversion done also could be an interrupt. I =

could make either or both high interrupts, but don't know whether that's =

the better way to handle it.

I could easily change the 8mz to 16 or 20, could it be I have run out of =

processing time? As for the output timing, that's not an issue, even at =

once a minute sending, is more than adequate, the items don't change =

that quckly.

By saving at interrupts, I now have the string array and index variables =

declared (global) before and outside any functions. I do not have  any =

compiler managed resources saved/unsaved.

As I am writing, Mike Rigby's message came in. In the receive interupt, =

I do have a receive buffer where the routine looks for the first =

incoming character of the RS-485 command, and then starts filling the =

array (7 characters),  when the required number of characters is =

received a strncmp() compares with the required string and sets a flag.  =

For the transmit I do build a string array (buffer), which I have been =

just using printf to send out the USART. I can change that to interrupt =

driven. The number of characters in the outgoing message is less than 20.

Jan-Erik S=F6derholm wrote:
> Carl Denk skrev:
>   =

>> I have an 18F1320 @ 8mhz. with RS-285 as slave on the USART, and 3 =

>> active ADC channels. The USART receive is a high priority interrupt,
>>     =

>
> Are *all* interrupts (used) high prio ?
>
>   =

>> I haven't been doing any special save at the interrupts.
>>     =

>
> Not even what's specified in the datasheet ?
>
>   =

>> What would be the appropriate way to handle interrupts and polling.
>> :)
>>     =

>
> First, to follow the datasheet...
>
> Then, to *not* use high/low interrupt prio's if not
> absolutely needed. Running with one level is much easier.
>
> Jan-Erik.
>
>   =

-- =

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