Lpc2000

Peter Homann wrote:

> The MSP is using the serial interface but is probably using the control
> signals for non serial control. If there is any timing required, it may
> be lost by the USB to serial converter.
>
> This is similar for programs that use the parallel port to control
> stepper motor drivers. The generated pulse streams are time critical.
> The USB-parallel converters don't give a stuff about the timing issue,
> and so the timing data is lost.

Another program is the USB timing. USB 1.1 has a 1 ms packet timing and 
USB 2 a 128 us timing.
This means that combined reading writing (e.g. set CLK, read MISO, clr 
CLK) will cost you 3 packets.
That's 3 ms on USB 1.1 and .375 ms on USB 2.

I tried using the FT245 as SPI/ISP port but stops my efforts when I 
discovered this.
FT245 is great if you're only doing output (or input) you can even 
specify a timing.

Rob