[fpc-pascal] Using Serial in a TCP/RS232 gateway, how to set buffer sizes?

Paul Breneman Paul2006 at BrenemanLabs.com
Thu Sep 7 02:40:47 CEST 2017

On 09/06/2017 05:21 PM, Marc Santhoff wrote:
> On Mi, 2017-09-06 at 23:06 +0200, Bo Berglund wrote:
>> On Wed, 06 Sep 2017 22:52:12 +0200, Bo Berglund
>> <bo.berglund at gmail.com> wrote:
>>> I have now added extra binary logging to the relaying program only to
>>> find that the data received and processed are missing about 50 k of
>>> the 1M transmission.
>>> Next I will edit serial.pp and up the buffers from 2K to 60K or so.
>> By the way:
>> I have sent the Delphi test program I am debugging over to people at
>> the remote location and they have connected their laptop directly to
>> the data system and with that setup there is no data loss.
>> So this leaves me with only the Lazarus/FPC network relaying app to
>> fix...
> Could that be some sort of timeout?
> You're setting
>    FTcpComm.ReadTimeout := 30;
> but I have no idea what order of magnitude this 30 is. Maybe streching
> the timeout a little bit can help?
> I had several cases of timeout problems using RS232 over TCP.
>> I could also create another test program, a serial sniffer that could
>> be set up to just log whatever appears on the serial lines. I need a
>> 3-way cable for that of course.
> Such thing does exists, I only forgot the name(s), ;)
> HTH,
> Marc

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