Re: StreamDevice/ASYN connection to a Telnet port

[Dirk Zimoch <dirk.zimoch@psi.ch>]

Hi John,

StreamDevice normally reads first a single byte and then the rest in 
chunks of up to 63 bytes. The reason is that the first byte uses a 
different timeout (ReplyTimeout) than the others (ReadTimeout). The rest 
is fetched in 63 bytes chunks because I use an internal buffer of 64 
bytes and want to be able to add a null byte at the end to avoid 
problems with some debug output.

So the first "read 1" is normal. What surprises me are the other lines.

When you switch on debugging in StreamDevice (var streamDebug 1), what 
do you see?

Dirk

John Dobbins wrote:
> Dear All,
>
> I am connecting to a Gamma Vacuum SPCe ion pump power supply. This device has an ethernet port which accepts telnet connections.
>
> I set up StremDevice to communicate with it on port 23,
>
> I have  asyn Trace Masks set as follows:
>
> asynSetTraceMask("SPCe",-1,0x09)
> asynSetTraceIOMask("SPCe",-1,0x2
>
> I have a problem in that the response string , which I expect to look like  "OK 00 7.90E-13 TORR" 
>
> appears like this:
>
>
> epics> 2011/01/17 16:14:55.995 172.18.32.21:23 write 7
> spc 0B\r
> 2011/01/17 16:14:56.475 172.18.32.21:23 read 1
> O
> 2011/01/17 16:14:56.475 172.18.32.21:23 read 1
> K
> 2011/01/17 16:14:56.475 172.18.32.21:23 read 1
>  
> 2011/01/17 16:14:56.475 172.18.32.21:23 read 1
> 0
> 2011/01/17 16:14:56.475 172.18.32.21:23 read 1
> 0
> 2011/01/17 16:14:56.476 172.18.32.21:23 read 1
>  
> 2011/01/17 16:14:56.476 172.18.32.21:23 read 1
> 7
> 2011/01/17 16:14:56.476 172.18.32.21:23 read 1
> .
> 2011/01/17 16:14:56.476 172.18.32.21:23 read 1
> 9
> 2011/01/17 16:14:56.477 172.18.32.21:23 read 1
> 0
> 2011/01/17 16:14:56.477 172.18.32.21:23 read 1
> E
> 2011/01/17 16:14:56.477 172.18.32.21:23 read 1
> -
> 2011/01/17 16:14:56.477 172.18.32.21:23 read 1
> 1
> 2011/01/17 16:14:56.478 172.18.32.21:23 read 1
> 3
> 2011/01/17 16:14:56.478 172.18.32.21:23 read 1
>  
> 2011/01/17 16:14:56.478 172.18.32.21:23 read 1
> T
> 2011/01/17 16:14:56.478 172.18.32.21:23 read 1
> O
> 2011/01/17 16:14:56.478 172.18.32.21:23 read 1
> R
> 2011/01/17 16:14:56.479 172.18.32.21:23 read 1
> R
> 2011/01/17 16:14:56.479 172.18.32.21:23 read 1
> \r
>
>
> Can someone tell me what is going on here?
>
> Regards and thanks,
>
> John Dobbins
>
> Cornell University
> Lab for Elementary Particle Physics