View Single Post
  #8  
Old 04-04-2011, 07:12 PM
BlueAstra (Graham)
Registered User

BlueAstra is offline
 
Join Date: Dec 2009
Location: Manchester, UK
Posts: 46
Another false lead! Just to recap, I’m trying to control my EQ6 mount locally with a small PC which is controlled via remote desktop from the house PC. The local PC is a ZBOX nettop and the house PC is the same (see earlier posts for spec). My problem with this layout is that with just about any combination of Serial EQDIR / USB EQDIR / Keyspan USB-Serial adapter on the local PC I get a communication loss either just after connecting or during a slew to a target. The control software is Maxim DL 5.14, Ascom 5.5.1, EQMOD 1.23e. However, if I use the handset in PC direct mode, the system works effectively, with just the occasional single comms error that doesn’t affect operation. It’s essential that I get the system working reliably if I am to progress to an observatory build. I have taken Maxim out without any improvement.

I’m sure the problem is in the local PC, but I can’t find it. The old desktop with a serial port does work with the in-line filter, and not reliably without it, but the filter doesn’t improve the other setups. I did actually get a single comms error event during parking with the desktop. I borrowed/have some other computers that work:

HP TX-2 laptop (AMD Turon x2dual core RM-74 @ 2.2GHz, 3G RAM, W Vista SP2 32bit) running Maxim 5.14, Ascom 5.0a, EQMOD 1.19g.

Acer Aspire Netbook (N270 @1.6GHz, 1G RAM, W7 Starter) running Maxim 5.1.4, Ascom 5.5.1, EQMOD 1.23e

I’ve noticed with the working PCs that the slew graphic in Maxim moves in regular jumps to the target. With the local PC, the jumps are very irregular in the failure setup, and slightly less irregular in the PC direct setup. Clicking on the Ascom logo in EQMOD for the command window shows the comms hesitates in synchronism with the irregular graphic jumps.

The Keyspan adapter includes a useful port monitor. This is an excerpt close to the comms error. ‘Buffer overrun’ doesn’t sound good, but I’ve no idea where the buffer is it’s talking about. You do get them on the good PCs, but maybe not as many.

18711: 17896 (80486 39.436.869): writeCompl (0/0)
18712: 17897 (80487 39.436.869): unknown 71 port (5/-2032336724) code 0 len 14 p1 0
18713: 17898 (80488 39.436.869): serdGetBuf (0/0) len 0 In 0 Out 0
18714: 17899 (80489 39.436.869): read/partial (0/0) req 1 act 0 (0)
18715: Events Request returned 5600 bytes (100 Records)
18716: *** Buffer Overrun ***
18717: 17900 (80495 39.452.469): read/complete (0/0) len 1 (00000033)
18718: 17901 (80496 39.452.469): serdStatus (0/0) MSR 00 cumErrs 00

So the investigation continues. Will keep you posted.
Reply With Quote