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Hi,

I try to figure out how I can get logging of power production out of a circle. Currently I have used linux only, on a synology NAS. I figured out how to convert the actual readings (1s, 8s, hourly) to negative numbers by adapting python-plugwise. However, the history logging (command/reply 0048/0049) results in zero's for each hour the solar panels produce. I have a couple of theory's:

1. I need to upgrade firmware before the logbuffers start containing negative values (requires windows to update firmware, mine is mid 2011).
2. There is a different command/reply set to read production logging.
3. The 0048/0049 command/reply need a different base address from 00044000.
4. Those values are not recorded in the plug. I need to read the 1s, 8s or hourly actual pulse counts.

So does someone have experience with this, or can share insights with me on this?

Frank

Update:

Options 3 and 4 can be removed from the list:
I found that I can dump the complete 512kB of memory of the plug by requesting the history buffer 16384 times. From the full memory dump I can see that there is no other memory space with hourly loggings.

I add option 5 to my list:
5. There is command to enable recording of negative (or production) values. This could be related to tariff settings.

So I am affraid that I just have to install Source and use a port sniffer to log the data streams to further analyze how to enable logging of production.

Enabling production data logging and controlling the log interval

...so I installed a serial port monitor and plugwise source 2.20 and configured one of the circles as being a producer. Between many commands/responses like 0012/0013 I observed the 0057 command which proved to be the enabler of logging production values: (Leaving out Start, CRC and End) The two parameters 0x3C are immidiatelly recognized as 60 for people who programmed embedded stuff in previous lifes. So I interpretted this as a log interval, being 60 minutes, the first for usage, the second for production. Later on, on my linux system I played with those values to proof this. This basically means that the minimal logging interval can be set to one minute. This function is not available form Source. The 0048/0049 get historic logging data now starts to return both positive and negative values.
Before the 0057 command, only production is logged (postive values around 000000EE=238 pulses/60 minutes) After aplying the 0057 command with 60, 60, the addressed space is interleaved with usage and production values: The set interval command does not have to have two identical values. When set to for example usage=10 minutes, production is 2 minutes, the buffer gets written with five (negative) production values, and then one usage value, as can be seen from the payload of three consequetive 0049 responses: So in general, production values are always logged as negative numbers. This also applies to the 0012/0013 command/repsons pair. In this command, the 1s-pulse-count and the 8-second-pulse-count can be both positive and negative, while the one-hour-pulse-count has a separate 32-bit number for usage, (zero or positive), followed by a 32-bit number for production (zero or negative).

Setting the interval
In source it cannot be controlled. One always get 60-minutes log interval. On Linux a circle can now be used to have a recording every minute from the log buffers. The advantage may be that one has a reasonably high resolution, while you do not have to have your computer turned on all the time. Another advantage is that one does not mis a value when software crashes, or a computer has to reboot or something (...hardly ever happens in linux)