Re: [StreamDevice] parsing rapid inputs

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

Hi Pavel,

Try to increase ReadTimeout. It seems that sometimes your device takes 
some time between sending the message and sending the \r.
Dirk


Pavel Masloff wrote:
> Hello,
>
> I have run into a problem lately. I have sort of a slow device - a 
> TDS2024 scope. So when I run my IOC, I expect StreamDevice to initialize 
> my PVs. So there are ~ 20 PVs I want to initialize. And every once in a 
> while I get the following error message in epics shell:
> /2012/05/30 13:02:25.211 L2 TDS2024:probe_ch2: got "<0d>:CH2:PROBE 1" 
> where ":CH2:PROBE " was expected
> /This <0d> character (or CR) is driving me mad. This is because it was 
> supposed to be the terminator of the previous input (here is the whole 
> string together with the one above):
> /2012/05/30 13:02:25.124 /dev/ttyUSB0 read 13
> :CH1:PROBE 1\n
> //2012/05/30 13:02:25.211 L2 TDS2024:probe_ch2: got "<0d>:CH2:PROBE 1" 
> where ":CH2:PROBE " was expected/
> As you can see, there is an \r missing. So my <0d> comes as a part of 
> the input /":CH2:PROBE 1" /- so I get /"<0d>:CH2:PROBE 1"  /instead 
> which causes the error.
> How can I fix this?
> I have tried using the @mismatch handler, but it doesn't work within the 
> @init handler.
> And you will never know which PV will not initialize next.
> As an comparison, my TPS2024 and TPS2024B scopes are fast enough to 
> stumble upon this. No problem there.
>
> --
> Best regards,
>
>
> Pavel Maslov, MS
> Controls Engineer at Pulsed power Lab
> Efremov Institute for Electro-Physical Apparatus
> St. Petersburg, Russia
>
> Mobile: +7 (951) 672 22 19
> Land line: +7 (812) 461 01 01