[Nut-upsdev] driver for IVT SCD solar controller ?

Thu Jul 30 19:26:41 UTC 2009

AdK> Please fix the permissions problem first, either by running this as  
AdK> root (should be OK for the time being) or by allowing whatever user  
AdK> this is running as permission to the /var/state/ups directory. I would  
AdK> really like to know what happens if you keep this running for a while.

OK, now running as root.

1st execution:
[root at test drivers]# ./ivtscd -DDDD -a ivtscd
Network UPS Tools - IVT Solar Controller driver 0.01 (2.4.1-1891)
Warning: This is an experimental driver.
Some features may not function correctly.

   0.000000     debug level is '4'
   0.002857     send: F
   0.388363     read:
   0.388853       \_: (42 bytes) => 00 52 3a 31 32 2c 31 32 3b 2d 20 33 2c 38 3b 31 37 3b
   0.389507      31 32 2c 30 31 3b 31 32 2c 36 32 3b 2d 20 36 2c 33 3b 20 30 2c 31 3b 0a
   0.390166     Parsed -1 parameters from reply
   0.390670     IVT Solar Controller not detected

2nd execution:
- if it is started more than a minute after the previous execution,
the same error as above occurs.
- if it is executed immediately again, it looks like this:
[root at test drivers]# ./ivtscd -DDDD -a ivtscd
Network UPS Tools - IVT Solar Controller driver 0.01 (2.4.1-1891)
Warning: This is an experimental driver.
Some features may not function correctly.

   0.000000     debug level is '4'
   0.002797     send: F
   0.365275     read: R:12,12;- 3,8;17;12,01;12,62;- 6,3; 0,1;
   0.365819       \_: (41 bytes) => 52 3a 31 32 2c 31 32 3b 2d 20 33 2c 38 3b 31 37 3b 31
   0.366526      32 2c 30 31 3b 31 32 2c 36 32 3b 2d 20 36 2c 33 3b 20 30 2c 31 3b 0a
   0.367082     Parsed 7 parameters from reply
   2.367926     send: F
   2.741239     read: R:12,12;- 3,8;17;12,01;12,62;- 6,3; 0,1;
   2.741332       \_: (41 bytes) => 52 3a 31 32 2c 31 32 3b 2d 20 33 2c 38 3b 31 37 3b 31
   2.741397      32 2c 30 31 3b 31 32 2c 36 32 3b 2d 20 36 2c 33 3b 20 30 2c 31 3b 0a
   2.741488     Parsed 7 parameters from reply
   2.742385     dstate_init: sock /var/state/ups/ivtscd-ivtscd open on fd 5
   2.742564     send: F
   2.749231     read:
   2.749745       \_: (1 bytes) => 0a
   3.750200     read: timeout
   4.742273     send: F
   5.112240     read: R:12,12;- 3,8;17;12,01;12,62;- 6,3; 0,1;
   5.112335       \_: (41 bytes) => 52 3a 31 32 2c 31 32 3b 2d 20 33 2c 38 3b 31 37 3b 31
   5.112400      32 2c 30 31 3b 31 32 2c 36 32 3b 2d 20 36 2c 33 3b 20 30 2c 31 3b 0a
   5.112491     Parsed 7 parameters from reply
   6.742273     send: F
   7.108242     read: R:12,12;- 3,8;17;12,01;12,62;- 6,3; 0,1;
   7.108338       \_: (41 bytes) => 52 3a 31 32 2c 31 32 3b 2d 20 33 2c 38 3b 31 37 3b 31
   7.108402      32 2c 30 31 3b 31 32 2c 36 32 3b 2d 20 36 2c 33 3b 20 30 2c 31 3b 0a
   7.108493     Parsed 7 parameters from reply
   8.742275     send: F
   9.148244     read: R:12,12;- 3,8;17;12,01;12,62;- 6,3; 0,1;
   9.148341       \_: (41 bytes) => 52 3a 31 32 2c 31 32 3b 2d 20 33 2c 38 3b 31 37 3b 31
   9.148405      32 2c 30 31 3b 31 32 2c 36 32 3b 2d 20 36 2c 33 3b 20 30 2c 31 3b 0a
   9.148497     Parsed 7 parameters from reply
  10.742274     send: F
  11.128247     read: R:12,12;- 3,8;17;12,01;12,62;- 6,3; 0,1;
  11.128341       \_: (41 bytes) => 52 3a 31 32 2c 31 32 3b 2d 20 33 2c 38 3b 31 37 3b 31
  11.128406      32 2c 30 31 3b 31 32 2c 36 32 3b 2d 20 36 2c 33 3b 20 30 2c 31 3b 0a
  11.128496     Parsed 7 parameters from reply
  12.742275     send: F
  13.125245     read: R:12,12;- 3,8;17;12,01;12,62;- 6,3; 0,1;
  13.125338       \_: (41 bytes) => 52 3a 31 32 2c 31 32 3b 2d 20 33 2c 38 3b 31 37 3b 31
  13.125402      32 2c 30 31 3b 31 32 2c 36 32 3b 2d 20 36 2c 33 3b 20 30 2c 31 3b 0a
  13.125495     Parsed 7 parameters from reply
  14.742274     send: F
  15.092242     read: R:12,12;- 3,8;17;12,01;12,62;- 6,3; 0,1;
  15.092338       \_: (41 bytes) => 52 3a 31 32 2c 31 32 3b 2d 20 33 2c 38 3b 31 37 3b 31
  15.092403      32 2c 30 31 3b 31 32 2c 36 32 3b 2d 20 36 2c 33 3b 20 30 2c 31 3b 0a
  15.092495     Parsed 7 parameters from reply
  16.742273     send: F
  17.129239     read: R:12,12;- 3,8;17;12,01;12,62;- 6,3; 0,1;
  17.129333       \_: (41 bytes) => 52 3a 31 32 2c 31 32 3b 2d 20 33 2c 38 3b 31 37 3b 31
  17.129398      32 2c 30 31 3b 31 32 2c 36 32 3b 2d 20 36 2c 33 3b 20 30 2c 31 3b 0a
  17.129488     Parsed 7 parameters from reply
  18.742274     send: F
  19.106247     read: R:12,12;- 3,8;17;12,01;12,62;- 6,3; 0,1;
  19.106345       \_: (41 bytes) => 52 3a 31 32 2c 31 32 3b 2d 20 33 2c 38 3b 31 37 3b 31
  19.106409      32 2c 30 31 3b 31 32 2c 36 32 3b 2d 20 36 2c 33 3b 20 30 2c 31 3b 0a
  19.106500     Parsed 7 parameters from reply
  20.742273     send: F
  21.103241     read: R:12,12;- 3,8;17;12,01;12,62;- 6,3; 0,1;
  21.103335       \_: (41 bytes) => 52 3a 31 32 2c 31 32 3b 2d 20 33 2c 38 3b 31 37 3b 31
  21.103399      32 2c 30 31 3b 31 32 2c 36 32 3b 2d 20 36 2c 33 3b 20 30 2c 31 3b 0a
  21.103490     Parsed 7 parameters from reply
^C  21.912826   Signal 2: exiting
[root at test drivers]#

AdK> It could be that we're beating the SCD to death by doing a query twice  
AdK> right after another. This should be resolved once the driver has
AdK> started up and it polls once every 2 seconds.
yes, it looks better now, except for first null byte in the first run.
(it's running for five minutes now and shows reasonable data).

AdK> I added a small delay to  
AdK> prevent this. It could also be that it is echoing the '\n' we send in  
AdK> the 'F' command. Maybe this isn't needed?
in minicom just press F without enter and the result comes
immediately, so there is no cr/lf required after the F.

AdK> You're sure this isn't some kind of ground loop?
yes, that's also my suspicion:
- when the power cord of the test PC is unplugged, load drops from -3.8 to -2.0
- when the network cable is also unplugged, load drops from -2.0 to -0.3
(that's a bit low for an atom N270 + 80GB HD on idle, but could be
reasonable)

AdK> If this is a mains
AdK> connected PC, double check the protective earth.
I connected the PC to a different socket in a different room, but got
the same result. 

AdK> It wouldn't be the  
AdK> first time that a device goes berserk because it can't handle the 50  
AdK> Hz current that is flowing in the green/yellow wire connection. Try  
AdK> connecting a laptop (no wall adapter attached) to rule this out.

unfortunately, none of my (working) laptops has a serial port anymore.
I'll need to read into this ground loop problem ...

tn & cu

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Unix gives you just enough rope to hang yourself -- and then a couple of more 
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(Eric Allman)
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