I was recently looking into setting up a serial interface between a
PC and the EVM board, in order to transfer data generated by a PC
application to the DSP.
However, the DSP56303 datasheet tells me that the minimum clock speed
that the SCI interface can handle (in synchronous mode) is 53.3ns,
which is still too slow for the intended application, since serial
transfer would mean a delay of 8x53.3ns everytime a transfer was
The data that needs to be transmitted is simply a digital bit
stream... that will need to be filtered, etc by the DSP once it is
transferred. I was therefore thinking of setting up a very simple
interface with 3 wires, between the PC COM port and the EVM board:
- one wire to transmit the data
- one wire for the EVM to ask for data
- one wire for the PC to tell the EVM that data is ready
Polling would take care of synchronizing the exchange.
Has anybody ever implemented anything like this ? Is it possible
(under a windows based machine) to access the COM port as a GPIO
port ??? and read/write to certain pins ?
If not, is there a way to configure the SCI of the DSP to transfer 1
bit at time instead of 8 ??