Thanks for your prompt and detailed reply
I have a Daktronics timing display and a Gill ultrasonic wind gauge
Both communicate with the FinishLynx PC using a USB-serial cable linked to a serial-bluetooth adapter.
The link works very well
Although it would be nice to have a'cheaper' timing display (clock), I am thinking now of a display which shows the output from the wind gauge automatically
These are available from Gill but are very expensive
The wind gauge has two DB9 (RS232) ports and the device outputs a series of bytes (about 18 bytes - only the middle 5 bytes carry the data) when it has acquired one set of data (race completed)
One port interacts with the FinishLynx PC and the other is (at the moment) unused
I hope to use the unused port to send data to the (planned) display
This would need only two digits with a permanently lit decimal point in between + a few LED for the '-' symbol where appropriate
This would be a lot easier to build
This display can be close to the wind gauge so can be linked with a physical cable
I know that I can add a RS232 module to the Raspberry - can that be used as an input, then transmitting that data to the LED segments?
Thanks for your help?