Subject:
|
Re: Building and decoding messages
|
Newsgroups:
|
lugnet.robotics
|
Date:
|
Tue, 22 Feb 2000 01:06:49 GMT
|
Viewed:
|
2733 times
|
| |
|
|
In article <FqAz8J.7C@lugnet.com>, "Dennis Clark" <dlc@verinet.com>
wrote:
> Hiya,
>
> Well, I'm back to my RCX message decoder project. But, I have a
> question.
> I know of the serial protocol for the individual data bytes, but I'm
> curious
> about the packet level checksum. A packet (for a message) looks like
> this:
> 55 FF 00 F7 08 <data> <~data> CS ~CS
>
> Using the message $12...
>
> If I add the bytes (mod FF) I get FF + F7 + 12, I get 08, but 09 is the
> correct checksum. Does this mean that the CS is Sum(bytes)+1?
The header of '55 ff 00' isn't counted in the checksum - just F7 + 12 =
09
Dave Baum
--
reply to: dbaum at enteract dot com
|
|
Message has 1 Reply:
Message is in Reply To:
 | | Building and decoding messages
|
| Hiya, Well, I'm back to my RCX message decoder project. But, I have a question. I know of the serial protocol for the individual data bytes, but I'm curious about the packet level checksum. A packet (for a message) looks like this: 55 FF 00 F7 08 (...) (27 years ago, 21-Feb-00, to lugnet.robotics)
|
3 Messages in This Thread:
 
- Entire Thread on One Page:
- Nested:
All | Brief | Compact | Dots
Linear:
All | Brief | Compact
This Message and its Replies on One Page:
- Nested:
All | Brief | Compact | Dots
Linear:
All | Brief | Compact
|
|
|
|
