[Nut-upsuser] N-Power MEV-3000LT compatibility report and problem

[Charles Lepple]

On Aug 11, 2013, at 2:12 PM, Александр Безруков wrote:

> I see no problem with how the device communicates the Blazer/Megatec protocol.
> I must have found a bug in the driver.

It is possible that the shutdown was tested with a different implementation of the protocol. What do you get from the "I" command?

On Aug 11, 2013, at 11:25 AM, Александр Безруков wrote:

> So I believe the compatibility list deserves two new lines.

Probably best to delay adding this to the HCL until we can get the driver to shut down the UPS properly.

> # /lib64/nut/blazer_ser -amv -k -DDD
> Network UPS Tools - Megatec/Q1 protocol serial driver 1.55 (2.6.5-Unversioned directory)
>    0.000000    debug level is '3'
>    0.108370    Initiating UPS shutdown
>    0.108561    send: 'C'
>    0.150967    read: 'NAK'
>    0.151021    instcmd: command [shutdown.stop] failed
>    0.151162    send: 'C'
>    0.193506    read: 'NAK'
>    0.193598    instcmd: command [shutdown.stop] failed
>    0.193725    send: 'C'
>    0.236016    read: 'NAK'
>    0.236093    instcmd: command [shutdown.stop] failed
>    0.236127    Shutdown failed!

This behavior (where any previous pending shutdown is cancelled first) was introduced here:

   https://github.com/networkupstools/nut/commit/0eef5be7

I wonder if other Megatec-based units don't send a NAK if there is no shutdown pending?

Also, maybe we can just attempt the 'C' command up to three times, then send the shutdown command outside that loop.

Unfortunately, my Best Power UPS is not available to see how it handles this.

Also, I am not at all familiar with the runtime calibration config variables.

-- 
Charles Lepple
clepple at gmail