Mike Harrison <mike <at> whitewing.co.uk> writes:

>=20
> Just prototyping  a device to read data from a USB stick on a  PIC24FJ64G=
B004,
using code adapted
> from the Microchip datalogger example, and the full (paid-for) compiler
version. Optimisations M2/M3
> Transfer rate seems a little disappointing - reading 2K blocks is taking
27.3ms, an overall rate
> around 75kbytes/sec. (51.2ms for 4096 bytes  =3D 80kbytes/sec).
> This is using FSfread call, reading sequentially from a large file with n=
o
seeks inbetween.
>=20
> This seems a little slow - anyone have any experience to comment on wheth=
er it
seems reasonable or
> could be improved ?
>=20
> I'd ideally like to be able to get closer to 200kbytes/sec, and if the PI=
C
won't do it will look at
> the VNC2L
>=20
Not speaking from experience with this particular system.
Could this time be mostly due to initialization/setup of the system for rea=
ding?
 How long does it take to read the next 4k block?=20
The actual read rate might be higher than that.=20

Sergey Dryga
http://beaglerobotics.com

--=20
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