Thread: STATUS_MESSAGES
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Old October 20th, 2009   #11
prwatE120
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Join Date: Jun 2006
Posts: 181
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Yes I've been here before with various Microchip PIC parts. In some (most) situations you run the risk of not being able to service irq's fast enough whilst the part is writing to EEprom. My approach, whilst still using ACK_TIMER to fend off the controller, was to buffer all my write requests and schedule them to occur when there was no pending RDM comms.

For those coding in a high level languague -

I would also look carefully at what your compiler library does in the routines to write to the EE. The one I used was horrible, masking interrupts for far longer than necessary, which did not help with the servicing of comms. I ended up having to create my own.

The RDMLabpack only needs to issue ACK_TIMER for SET: commands that result in EE writes. The ACK_TIMER tells the controller that the original request has been received, has the correct syntax and has been understood. It will get actioned. If there were to be a subsequent Write problem, I would generally choose to que a STATUS_MESSAGE with an appropriate error code.

Berntd - if you contact me off-list I can send you more details of the Labpack.

Peter
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