On 22/10/10 23:07, Philip Pemberton wrote:
> Is anyone aware of any 'gotchas' with the FT245R (or its predecessors in
> the FT245B series) which could cause this?

Fixed it!

SUMMARY: FT245R data outputs stuck high, FIFO control lines misbehaving

FT245R USB-FIFO chips may fail in a way which leaves the data I/O lines=20
stuck high, and the RXF# / TXE# flag lines either stuck low or in random=20
states (toggling H/L incorrectly, etc.)

CAUSE: Failed FT245R IC
Possibly caused by lack of VCCIO when VCC comes up, or EEPROM corruption.

RESOLUTION: Attempt to restore EEPROM image to default (see ROM dump=20
below). If this fails, replace FT245R IC.

EEPROM dump from a brand-new FT245R (for the benefit of anyone playing=20
with the FTDI EEPROM flasher tool!):

> FTDI chipid: B10B74F9
> =3D=3D=3D EEPROM test =3D=3D=3D
>   VID 0x0403
>   PID 0x6001
>   HW Version 0x0000
>   USB Flags 0xA0
>   Power 0x2D
>   FTDI Flags 0x08
>   EEPROM dump:
>     0000: 01 40 03 04 01 60 00 00 A0 2D 08 00 00 00 98 0A    .@...`...-..=
.....
>     0010: A2 20 C2 12 23 10 05 00 0A 03 46 00 54 00 44 00    . ..#.....F.=
T.D.
>     0020: 49 00 20 03 46 00 54 00 32 00 34 00 35 00 52 00    I. .F.T.2.4.=
5.R.
>     0030: 20 00 55 00 53 00 42 00 20 00 46 00 49 00 46 00     .U.S.B. .F.=
I.F.
>     0040: 4F 00 12 03 41 00 39 00 30 00 30 00 33 00 4D 00    O...A.9.0.0.=
3.M.
>     0050: 70 00 55 00 60 BF 0D 90 00 00 00 00 00 00 00 00    p.U.`.......=
.....
>     0060: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00    ............=
.....
>     0070: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 7B 34    ............=
...{4
>
> RAW HEX DATA:
> 01 40 03 04 01 60 00 00 A0 2D 08 00 00 00 98 0A
> A2 20 C2 12 23 10 05 00 0A 03 46 00 54 00 44 00
> 49 00 20 03 46 00 54 00 32 00 34 00 35 00 52 00
> 20 00 55 00 53 00 42 00 20 00 46 00 49 00 46 00
> 4F 00 12 03 41 00 39 00 30 00 30 00 33 00 4D 00
> 70 00 55 00 60 BF 0D 90 00 00 00 00 00 00 00 00
> 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
> 00 00 00 00 00 00 00 00 00 00 00 00 00 00 7B 34

--=20
Phil.
piclist@philpem.me.uk
http://www.philpem.me.uk/
--=20
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