E1.20 RDM (Remote Device Management) Protocol Forums  

Go Back   E1.20 RDM (Remote Device Management) Protocol Forums > RDM Developer Forums > RDM Interpretation Questions

RDM Interpretation Questions Discussion and questions relating to interpreting and understanding the E1.20 RDM Standard.

 
 
Thread Tools Search this Thread Display Modes
Prev Previous Post   Next Post Next
Old November 14th, 2018   #1
shawn
Junior Member
 
Join Date: Nov 2018
Location: Oakland, CA, USA
Posts: 19
Default When locked, which comes first, NR_WRITE_PROTECT or message checking?

I have a question about the interpretation of when to send a NR_WRITE_PROTECT NACK response when a device is in a locked state.

When a device is in some lock state, E1.37-1 says that it should return NR_WRITE_PROTECT for those PID's that require locking. Should this be returned before even looking at a message, or should the message first be examined for format or content errors and then the NR_WRITE_PROTECT sent?

There are really three cases for when a message/PID gets denied. Either it has an unknown PID, the command class is not supported, or it has some bad formatting or content errors. The question of when to send the NR_WRITE_PROTECT arises for all three.

If we send the NR_WRITE_PROTECT first, it makes the code easier to write, because there's only one check at the top. If it's sent only after a message is checked (with associated potential NR_UNKNOWN_PID, NR_UNSUPPORTED_COMMAND_CLASS, or NR_FORMAT_ERROR/NR_DATA_OUT_OF_RANGE), then those other errors have priority and are returned first.

Thoughts?
shawn is offline   Reply With Quote
 

Bookmarks

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Queued Message for SubDevices sandor RDM Interpretation Questions 2 May 14th, 2018 02:10 AM
Status Message Markers hamish RDM General Implementation Discussion 4 December 9th, 2010 11:12 PM


All times are GMT -6. The time now is 08:46 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2024, vBulletin Solutions, Inc.