SBus development notes
Herein are included a few notes that might be useful for people working with SBus.
- SBus is actually two standards. The term "SBus" may refer to either the SBus22 standard, or the standards shared between them. The other standard is SBus32, which is more expensive and has a slightly higher chance of error, but can be up to 30% faster. When the usage is unclear, please specify either "the SBus family" or "SBus22".
- The SBus website (if you aren't currently on it) is http://sbus.sf.net. It has links to info and downloads, as well as lots of licensing info.
- Please report all bugs/errors to the SBus project lead developer (John Ohno)
- All SBus schematics are in an extended version of the Verilog netlist format, as used by TkGate version 1.6i. You can probably use the code with normal Verilog programs, and it will still work under most circumstances, however you will have lost the ability to view the schematics visually.
- The TkGate website may be found here, where you may download and view documentation, source, binaries, and examples
- The SBus22 changed between revision 0 and 1 of the standard because of a pin number recalculation. The TINT and RINT pins were added in slots that were found to be empty.
- The SBus32 does not have TINT and RINT pins, and the TCK and RCK pins are tied to ground.
- The SBus32 transfers 32 bytes at a time per duplex, over 32 serial lines. The SBus22 does 22 bytes over 22 lines.
- The firmware is written primarily in C and by Doug Bray, using AVRlibc and GNU compilers/assemblers. We have not yet released a version.
- You may use the standard UNIX serial driver for interaction with an SBus interface, however you will then need a userspace program for decoding the frames. Alternately, you may use the custom SBus driver with the normal IP stack and standard applications and utilities.