... | ... | @@ -51,9 +51,7 @@ It declares the frequency at which one bit is transfered. Regarding the OpenLab |
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The receiving part of the UART implementation is directly connected to the RX line of the Transistor–Transistor Logic (TTL) serial adapter cable.
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This component detects incoming data by checking continually the status of the RX line. If it detects an falling edge, data is being sent to the FPGA.
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This is also known as the start bit of the serial communication, which is described in section 5.3.1.
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For correctly interpreting the sequence of bits, the FPGA has to store the information at the frequency of the baud rate.
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For example, to receive data at 1 MBaud, the system clock of the OpenLab FPGA design hast to be clocked down to 1 MHz. This is done by implementing a simple clock divider.
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At each clock cycle one bit of the received data package is stored into a register. After the stop bit was received, the "FINISHED" flag is set and the data is ready for further processing.
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== Transmit Component
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