I'm working on a new customized motor controller system I've inherited. The system has a heirarchy of controllers - a PC communicates to an RS-485 serial bus of one level of controllers, and each one of these communicates to it's own RS-485 bus of controllers. The system uses a customized packet protocol with simple 8 bit checksum and no ACK/NAK scheme. Maximum packet length is 256 bytes. I'd like to come up with a really thorough communications test for the system, one I could leave running for perhaps hours on a system testing it as much as possible for any type of data corruption. What would be the ideal way to do this? Would it be better to test a known data pattern, or pseudo random data? If a known data pattern, what should the pattern be? Would it be better to test short data packets or maximum length packets or varying combinations? I know there are a lot of good algorithms out there for testing RAM so am eager to learn of how to best test serial interfaces.

Thanks for any answers, Fred

I'm working on a new customized motor controller system I've inherited. The system has a heirarchy of controllers - a PC communicates to an RS-485 serial bus of one level of controllers, and each one of these communicates to it's own RS-485 bus of controllers. The system uses a customized packet protocol with simple 8 bit checksum and no ACK/NAK scheme. Maximum packet length is 256 bytes. I'd like to come up with a really thorough communications test for the system, one I could leave running for perhaps hours on a system testing it as much as possible for any type of data corruption. What would be the ideal way to do this? Would it be better to test a known data pattern, or pseudo random data? If a known data pattern, what should the pattern be? Would it be better to test short data packets or maximum length packets or varying combinations? I know there are a lot of good algorithms out there for testing RAM so am eager to learn of how to best test serial interfaces.