Electronics Forum / Basics / August 2006

Hi,

I'm writing a program that interfaces with a device on the serial port and
in the documentation it says the folowing:
3.1.1.   Header:Code.

The Header:Code combination is configured thus:

Header: 7   6   5   4   3   2   1   0

     < Number of Dims>   1  F/A E/S

Where:

Number of Dims is a value between 0 and 22 identifying the number of dims to
be transmitted (22 is equivalent to 100%)

Bit 2 is always set to '1' to ensure that the interface is able to maintain
synchronization.

F/A defines whether the following byte is a function (1) or address (0).

E/S defines whether the following byte is an extended transmission (1) or a
standard transmission (0).

Could someone please explain what "Number of Dims is a value between 0 and
22 identifying the number of dims to be transmitted (22 is equivalent to
100%)" means?

A link to the documentation:
http://www.marmitek.com/en/software/PROTOCOL.DOC (Bottom of page 2)

Thanks,

Michael