Menu
RS-232 communication sometimes uses 9-bit bytes. This can be used to communicate with multiple microcontrollers on a bus where 8 bits are data and the extra bit indicates an address byte (rather than data). Inactive controllers only generate an interrupt for address bytes.
Can a Linux program send and receive 9-bit bytes over a serial device? How?
831
Most serial ports use between five and eight data bits. Binary data is typically transmitted as eight bits. Text-based data is transmitted as either seven bits or eight bits.
SBUF is an 8-bit register used solely for serial communication in the 8051. For a byte of data to be transferred via the TxD line, it must be placed in the SBUF register. Similarly, SBUF holds the byte of data when it is received by the RxD line. SBUF can be accessed like any other register in the 8051.
In serial communication, data is transmitted one bit at a time (Figure 4.20a). Thus if an 8-bit word is to be transmitted, the 8 bits are transmitted one at a time in sequence along a cable.
I also made complete demo for 9-bit UART emulation (based on even/odd parity). You can find it here.
All sources available on git.
You can easily adapt it for your device. Hope you like it.
118
9-bit data framing is possible even if a real world UARTs doesn't. Found one library that also does it under Windows and Linux. See http://adontec.com/9-bit-serial-communication.htm
44
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With
