Serial Extended Level Parsing

Hi,

Long-time reader, first time poster.

I've been working with the serial protocol for a while, and have come up against something I just can't figure out. I'm hoping that someone with superior knowledge can tell me!

I'm requesting the status levels and getting back the nibble pairs. Where I'm falling short is being able to mathematically translate these to a group level. In the doco(pg.48), they state that;

• $5=11
• $6=10
• $9=01
• $A=11

How!? The document describes this conversion as nibble->binary. The second step from binary to hex isn't an issue.

Any ideas would be greatly appreciated!

Cheers,
Ben

 

A "5" in the status reply represents a binary value of 11. A "6" represents binary 10 and so on. There is a good reason for this, but it isn't important for understanding how to do the decoding.

So if there is a "56" in the status reply, this is equivalent to binary 1110 or hexadecimal "E".

The example provided shows the rest of the details for decoding a full message.

 

Hi Darren,

Thanks for the response. I understand what you mean, and I've got no problems manually decoding it via the table/method on pg 48 of that doc, the issue I have is doing it programatically without using textual replacements.

Surely there must be a mathematical correlation for this first step? Once the nibble pairs are converted to binary, the hex conversion is easy.

Cheers,
Ben