Data logging

Rabbit
1

Hello people,

I have BL2600 with RCM3200. And I am new to this… Infact new to Dynamic C. I want to store some numbers coming from Analog Input channels and digital IO channels… Anyone care to explain in short… with reference and commands???

Thanks.

2

If you want to see an example of datalogging with a Rabbit SBC have a look at https://sourceforge.net/projects/bacrabbit/

This project implements BACnet/IP on a BL4S100 board and includes the trend log object for data logging. Using this in conjunction with the BACnet stack at https://sourceforge.net/projects/bacnet/ would give you a means of retrieving the data from the SBC without too much more effort.

I don’t know how much effort it would take to implement it on the BL2600 but I imagine it would not be too much work - I haven’t tried to do anything too exotic or too board specific on the BL4S100 port.

Regards,
Peter

3

I have a number of applications that do data logging. Essentially you are taking a snapshot of the system status at a certain time. Here is what I use:

struct
{
long inputs;
long outputs;
unsigned int analog[8];
} dataset;

This allows me to store up to 32 inputs, 32 outputs, and 8 analog channels in only 24 bytes. Each input and output is stored as a single bit in the long variable. Analog values are scaled from 0.00 to 1.000 and then multiplied by 65535, and stored as a short int. This gives you 16 bits of resolution for a 12 bit value.

I then create an array of these data sets. Once the array is full, then I transmit the set to a PC, by either serial or TCP/IP.

I use realtime kernel to collect data at a certain rate.

Hope this helps. Regards, David E.