High speed serial safety?

Scott M

I'd like to have one Javelin talk to another through 2-3 inches of wire, using Uart and serial communication. However, I'd like the communication to happen as quickly as possible - there will be lots and lots of bytes flowing at irregular intervals. It looks like there are constants for class Uart that go up to 57600 baud.

1) Is that going to work?

2) Do I need to take special precautions with the wire connection between the two (wrapping the length in grounded metal foil, etc). The environment is likely to be noisy (oscillators and radio receivers on the same board) and I *really* don't want bad bits introduced.

Voice of experience appreciated. Thanks.

(Note that adding a checksum to the message protocol is an approach I want to avoid.)

Peter Verkaik

Sending is reliable up to 57600, receiving up to 28800.

So if you use 2 javelin, do not exceed 28800.

I myself communicate between a SX28 and a Javelin

(both mounted on the same board) without checksums.

I have not encountered any problems. There are also

two 20MHz resonators and a 32kHz crystal on that board.

But if possible, add ground traces between signal

traces. That never hearts.

regards peter

Javalin

Hi Peter,

Have you any thoughts on using·36400?· I am talking using a Javalin to act as an intermediery between an EB500 blue-tooth module and a CMU2 CAM (which only runs at 19200 or 36400 - no 28800!)

Thanks

James

Peter Verkaik

Transmitting at 38400 is no problem.

There are occasionally bytes missed when receiving at 38499.

However, if you· implement a frame error check on a higher level,

and be able to request a block resend, then you should gain throughput.

(that is, between the receive buffer and the RF transmitter). You stil

can not read bytes into memory faster than approx.·10k baud.

regards peter
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