SCI Interface and Hardware Implementation of TMS320C6711D

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SCI Interface and Hardware Implementation of TMS320C6711D [Copy link]

The SCI module supports communication between the CPU and other asynchronous devices using standard formats. It has two I/O pins, SCIRXD (serial data receiving end) and SCITXD (serial data transmitting end). In full-duplex mode, it has a transmitter (including SCITX2BUF and its main register TXSHF) and a receiver (including SCIRXBUF and its RXSHF). The transmitter stores the data to be sent in SCITXBUF and shifts the data to the SCITXD pin one bit at a time; when receiving, it shifts the data on the SCIRXD pin one bit at a time, loads SCIRXBUF and SCIRXEMU for the CPU to read. It has a programmable baud rate generator that can obtain more than 65,000 different programmable rates. SCI provides independent interrupt requests and interrupt vectors for the receiver and transmitter: If the RX/BKINT ENA bit (SCICTL2.1) is set, when the SCI receives a complete frame and transfers the data in RXSHF to SCIRXBUF, this action sets the RXRDY flag (SCIRXST.6) and starts an interrupt. If the TX INT ENA bit (SCICTL2.0) is set, at any time, as long as the data in SCITXBUF is sent to TXSHF, the transmitter interrupt will be recognized, indicating that the CPU can write to SCITXBUF. This action sets the TXRDY flag and starts an interrupt. When TMS320C6711D and TMS320LF2407A perform standard asynchronous serial communication, the SCI interface of TMS320LF2407A can directly support the communication. You only need to configure the SCI interface to the serial interface mode through the internal special function register. In addition to configuring the McBSP of TMS320C6711D as a serial interface through the internal special function register, the hardware design should also short DR and FSR and connect it to the serial data transmission pin (SCITXD) of SCI. This is because the data line in standard asynchronous serial communication contains both frame synchronization information and data information. The serial data receiving pin (SCIRXD) of SCI is connected to DX of McBSP.