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10 years, 7 months ago.
What is the maximum bit stream speed which i can get experimantalyy of a micro-controller LPC1768
I want to use LPC1768 in a high speed data transmission. I want to send a serial bit stream at 10Mbps as a input of it. After that it will make a code with 2 bit and depends upon this code it will give the output as a 5 parallel bit stream from 5 port at 5Mbps. Is it possible experimentally?
1 Answer
10 years, 7 months ago.
Is the data synchronous to a clock?
An SPI serial stream can run at 20Mbps but needs a clock signal. There are also limits on how many bits you can send/receive before there is a slight pause. The BurstSPI library will minimise this pause but not completely eliminate it.
The UARTs will handle 1M baud with the appropriate framing but not 10M.
I can't think of any way to handle that sort of data rate without using an SPI or similar interface, it's far to fast to bit bash using GPIO pins. That also means that even if you do use SPI you're limited to the number of SPI interfaces on the CPU, IIRC the LPC1768 has 2.
The LPC1768 can run SPI up to 48mbps (50 if you run clock at 100MHz). It uses the SSP peripheral instead of legacy SPI which is bit faster. Bit banging can be done in a few clock cycles per write, so it is possible. Using DMA makes it 'easier' to do.
However, this is only something you should attempt to do if you are comfortable with addressing the MCU registers directly and writing everything from scratch. No way the mbed functions will handle this.
posted by 10 Apr 2015