Internet PLC Forum

Thanks I'll try that

Well I decided on a "go between."

Within the custfunction I make a pause for 400 ms after every 50 records.

This has been working flawlessly for some weeks now.

Thanks for the advice

Hi There,

I have 5  pcs T100MD888 connected to Fargo Telecom Mobile modems and one Windows server also connected to a Fargo Telecom Mobile modem. All modems are running at 9600 Baud
Once per day or when the DM[] variable reaches a threshold, each plc Modem dials the server modem and dumps the DM[]  ( in a padded format) and reads the RTC.

I use the Trilogi server version 2.0 and  the standard dial modem function supplied by Trilogi.

When sending  the data to the modem it is converted  ? on the fly? to text with zeros being padded and some hyphens and commas are added  as date and field delimiters and a CR for every 10 values in the DM.
Each Record is 10 positions in the DM as follows:
DM[1] = Date, DM[2] = Month, DM[3] = Year, DM[4] = Hour, DM[5] = Minute, DM[6] = Second, DM[7] = Value, DM[8] = ID, DM[9] = Value, DM[10] = Spare,

i.e if the DM Variable looks like this
18 3 2008 9 14 26 1 139 0
18 3 2008 9  9 26 2 139 0
18 3 2008 9  9 26 3 139 0
18 3 2008 9  9 26 1 139 0

it will be sent as records like this

18-03-2008,09:14:26,1,139,0 [CR]
18-03-2008,09:09:26,2,139,0 [CR]
18-03-2008,09:09:26,3,139,0 [CR]
18-03-2008,09:09:26,1,139,0 [CR]

This works and has been working fine for more that 12 months, as long as the DM[] is not filled beyond DM[1500]
If there is more data then some data is lost , not much just a comma or a few characters, but of course enough to corrupt data., and messing up the import rutine on the server
Until now I have solved it by sending data as soon as the DM[] variable reaches 1400 positions.
But now I will be installing at a site where the DM[] will fill up completely 2-3 times a day. So I have to solve the problem., because dialing up 5-10 times per day is to expensive, and the PLC is blocked during the process

I now guess the corruption is due to a buffer overflow I therefore introduced a 400 ms pause  for every 50 records being sent, by adding the following in my ?send and format data? procedure

If Y MOD 500= 1 then
Delay 400
End if

This actually works ( have tried  filling up the DM[] to positions 3840 10 times and transferring data), but prolongs the transfer time by 3 seconds in which the PLC is inactive

But I am worried about using the Delay function, would it be better to make at For Next loop to create a pause in the flow or is there another way of reducing the speed of dataflow?

/PeterH

Great Thanks,

wil try that out next week

/Peter

Great Thanks,  "<100uA" is what the manual states, so I'll try

Make a circuit (rung) with an input and a time special bit to prevent contact chatter.

Hi Cdenk,

Thanks for the info. I was just going write a normal diff function until you wrote the above. What do you mean by a time special bit? I hadn't thought of  noise interfering.

Best regards
Peter

I have blown two RTCs on two different T100MD last week and had to change the RTCs. After changing the RTC and connecting to power - output 6 has been activated and I have had to RESET the unit. I have dones this by downloading the  programme again and clicking  YES to Reset.
But is it possible to RESET the unit without a pc?
Maybe I missed something in the manual

Best Regards

Peter

I got a new bunch of transmission errors today.....

This makes me think:

Is there any error control between the PLC and TLServer. i.e is there a for example a CRC control of the flow when I issue a Print#1 " Appendxxx.txt" and send data to TL Server, or is data just sent out in the blue air and then presumed OK if I receive an <OK> after the Print#1"/" command?

Best regards

Peter