9-Bit Serial Data Communication

Transfering 9-Bit serial data frames

Serial communication with 9-Bit framing (9-Bit protocol, 9 bit mode) is mainly used to identify the address byte within messages running on a RS-485 multidrop network but also on standard RS-232 connections.

On a RS-485 network the Computer (PC) usually controls one or many remote devices (e.g. micro controllers) e.g. polling for status, data etc. .

There is also often the requirement that the PC should act as server thus simulating a device and receive and handle 9-bit frames and respond accordingly.

9-bit data frames are usually not supported by the PC UART but are provided by the SuperCom software (Windows and Linux). A very fast response time is particularly important here in order to achieve stable data communication. SuperCom offers a fast working and reliable solution for use with high level programming languages.

The SuperCom software can be used to build both parts of the data communication (computer side or device side of the connection - client/server).

Many Samples (e.g. for C/C++, C#, Delphi, Pascal, VB net) included in SuperCom serial library that demonstrate this operating mode.

For example, transmitting a data packet using 9-bit addressing e.g.:

        TXPacket9BitCond(Com, cData, nDataCount, SEC0_1);

NOTE: The DEMO software found online, even when activating RS-485 or 9-bit are working with limited functionality, especially when it comes to response timing and 9-bit which is not included in the DEMO. The complete functionality is contained only in the licensed version.

Example Programs:
9-Bit data communication is demonstrated by many example programs (client and server) written with C/C++, C#, Delphi, Pascal, VB net. The SuperCom Suite ships with an additional samples pack including special sample programs demonstrating 9-bit background data collection and event-driven 9-bit data capture. The event-driven working mode facilitates integration in a so-called Slave application. The data acquisition works quite independently of the GUI without blocking other processes.

The event-driven 9-bit working mode is used in many different types of projects e.g. controlling many embedded devices on a multidrop network. The event-driven 9-bit working mode is also very handy if it comes to control gaming machines using special data communication protocols (e.g. SAS Serial Protocol* and other protocols).

* Slot Accounting System (SAS) protocol. A special serial data communication protocol, that is often used to query gaming machines using EIA 232 serial port connections.

Free Tech Support
And as with every SuperCom, it comes with free tech support, so you're never alone with difficult questions.

What to order?
SuperCom's 9-Bit serial data communication capabilities are included in the 32 and 64 bit version of SuperCom Serial Library for Windows and in the SuperCom Suite for Windows. Also included in the 32 and 64 bit version of SuperCom for Linux and SuperCom for Linux ARM CPU.