• The 8051 microcontroller has an internal serial port, which can be operated in four modes.
• The baud rates for serial communication are programmable using internal Timer-1 of the 8051 controller.
• The 8051 controller can be used as full duplex serial communication device.
• A simple schematic for serial communication using 8051 is shown.
• The system requires a 8x5x microcontroller with internal program memory and RS232 level converter like MAX 232.
• A quartz crystal and a reset circuit should be connected to controller.
• The program for serial communication can be stored permanently in internal ROM and so there is no need for external memory. In case if 8031 controller is used then an external EPROM has to be interfaced for program storage.
• The serial bus is formed by using only three lines TxD, RxD and Vss (Ground).
• The signals TxD and RxD will have TTL logic levels and they can be converted to standard RS232 logic levels using bidirectional level converter MAX 232.
• The RS232 level serial port signal can be terminated on a standard 9-pin D-type connector, so that any standard serial device can be connected to 8051 controller for serial communication.
• The parallel data transfer can be achieved through ports.
• The parallel input data is received through port-2 and parallel output data is send through port-1.
• The controller can receive parallel data from an ADC and convert it to serial and transmit via serial port to another serial device. Also the controller can receive a serial data from another serial device via serial port and convert to parallel, and then output through port-1 to a parallel device like DAC.
• The 8051 controller supports full duplex communication and so the transmission and reception can be performed simultaneously.
• The baud rates for serial communication are programmable using internal Timer-1 of the 8051 controller.
• The 8051 controller can be used as full duplex serial communication device.
• A simple schematic for serial communication using 8051 is shown.
• The system requires a 8x5x microcontroller with internal program memory and RS232 level converter like MAX 232.
• A quartz crystal and a reset circuit should be connected to controller.
• The program for serial communication can be stored permanently in internal ROM and so there is no need for external memory. In case if 8031 controller is used then an external EPROM has to be interfaced for program storage.
• The serial bus is formed by using only three lines TxD, RxD and Vss (Ground).
• The signals TxD and RxD will have TTL logic levels and they can be converted to standard RS232 logic levels using bidirectional level converter MAX 232.
• The RS232 level serial port signal can be terminated on a standard 9-pin D-type connector, so that any standard serial device can be connected to 8051 controller for serial communication.
• The parallel data transfer can be achieved through ports.
• The parallel input data is received through port-2 and parallel output data is send through port-1.
• The controller can receive parallel data from an ADC and convert it to serial and transmit via serial port to another serial device. Also the controller can receive a serial data from another serial device via serial port and convert to parallel, and then output through port-1 to a parallel device like DAC.
• The 8051 controller supports full duplex communication and so the transmission and reception can be performed simultaneously.
