Dave VanHorn wrote:
>=20
> At 11:57 AM 11/10/2004, Ian Smith-Heisters wrote:
>=20
> >Shawn Tan Ser Ngiap wrote:
> >
> >>It has the same performance as the old 232BM FTDI chips.. Hey, I'm
> >>interested to find out if anyone knows if we can use the newer FT2232=
C to
> >>effectively double our bandwidth??
> >>
> >If a chip like this converts from the PIC UART to USB, how can you
> >increase the bandwidth? It would seem to me that it would still be lim=
ited
> >by the speed of the UART. Would you just output on more pins than the
> >PIC's default TX/RX?
>=20
> Nothing's going to speed up the pic uart.

Well, with 16Mhz and set SPBRG to 0 you get 1000 kbaud.
Pick a nice crystal rate (19.6608Mhz), and you can get=20
nice standard baud rates with bigger SPBRG values.

> All it can affect is speed on the USB bus, or the baud rates that the U=
SB
> chip is capable of.
>=20
> What would be REALLY nice, is a clocked serial or SPI version, so you d=
on't
> have to wait around for the uart to beedle the data out.=20

You mean like this?

http://www.ftdichip.com/FTProduct.htm

"The FT2232C is the 3rd generation of FTDI=92s popular USB=20
UART / FIFO I.C. family. This device features two=20
Multi-Purpose UART / FIFO controllers which can be
configured individually in several different modes.=20
As well as a UART interface, FIFO interface and=20
Bit-Bang IO modes of the 2nd generation FT232BM and
FT245BM devices, the FT2232C offers a variety of=20
additional new modes of operation, including a=20
Multi-Protocol Synchronous Serial Engine interface which is
designed specifically for synchronous serial protocols such as JTAG and S=
PI
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^=
^^
bus.
"

> Uarts are not well suited for on-board inter-processor communication.

They cerainly are not, but they can be pushed.

Robert
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