Baud rate intermessage timing issue and coil/digital register problem.

[GoogleCodeExporter]

What steps will reproduce the problem?
1.
Run it with any baud rate above 19200. Use it with > 8 coil or digital 
registers.

2.
Inter-message timing calculation is not right for all baud rates, refer 
http://www.modbus.org/docs/Modbus_over_serial_line_V1_02.pdf page 13. 

The existing code uses baud as type word, which has max value of 65535, 
therefore any baud over that doesn't work. 

Also above 19200, inter-message delay should be 1750ms (Fixed). 

3.
Coil and digital types only populate one byte for return packet (equivalent to 
8 contiguous digital or coil registers).

What is the expected output? - Non-fragmented messages above 19200 baud and 
ability to utilise 100+ coil and digital registers. 

What do you see instead? fragmented messages above 19200 and only the first 8 
contiguous digital or coil registers are returned to master.

What version of the product are you using? - Version 0.01b.

On what operating system? - Arduino

Please provide any additional information below.
See files attached for fixes that work for my application.
I have tested at 19200, 38400 and 115200 and packets look okay. 
I have also tested with 100 coil registers and all are returned correctly. 
Need to test digis and i suspect that analogues have similar issue.
Cheers, Ben

Original issue reported on code.google.com by Sys...@gmail.com on 18 Nov 2014 at 1:32

Attachments:

• MODBUS.zip

[GoogleCodeExporter]

Correction:
Inter-frame delay should be 1750us or 1.75ms.

Original comment by Sys...@gmail.com on 18 Nov 2014 at 2:08