Re: FTDI2232D & SPI
- From: "Bill Davy" <Bill@xxxxxxxxxxxxxxx>
- Date: Fri, 30 May 2008 11:48:19 +0100
"The Real Andy" <therealandy@xxxxxxxxxx> wrote in message
news:qkgv3491md87qeeeu6hoii3f2k7dm3gn9t@xxxxxxxxxx
On Fri, 30 May 2008 09:40:17 +0100, "Bill Davy" <Bill@xxxxxxxxxxxxxxx>
wrote:
I've been trying to get this working so far without success. I'm just
wondering if anyone else has. Our particular requirement is for the 2232
to
act as a master to a SiLab MCU acting as a slave. All transactions are
bytes. I've not got so far as worrying about CLKPOL or CLKPHA - right
now,
when I ask the 2232 to send data, SCK waggles like a good 'un, with small
gaps at byte boundaries, but the bytes I send do not appear on DO (or DI)
which may make a transition at byte boundaries (but never during the byte
as
I'd like).
I am confident we are in MPSSE mode because when I send 0xAA, I do get
0xFA
0xAA back.
I have checked each output bit individually to make sure they can be high
and low.
We are not using CS as this is a hard-wired point-to-point connection.
We are actually using the 2232 in a DLP-2232M-G for prototyping.
Programmed in C++, it is pretty simple code and (frankly, but I would say
this), I do not think this is where the problem is. I've listed what I am
sending and it all looks good. But is there something I may have missed?
Is there any set-up I could have missed (I do FT_ResetDevice() and then
SetBitMode(2) to get it into MPSSE mode and as I say above, I am confident
this has been successful).
I use a dlp2232 to read the CID block from an SD card using SPI. Works
a treat. THe only grief I had was getting the right data to the SD
card! Everything I sent to the 2322 went out the SPI port as expected.
Are you using the DLL and examples provided by FTDI? Thats what I did.
Ended up using c# in the end, but the c++ examples work a treat.
I did struggle a bit deciding which DLL to use.
As I was using SPI I started off looking at FTCSPI Programmer's Guide but it
seemed to be obsessed with sending sub-byte data (control fields). As we
have a byte only MCU as a slave that seemed to be more trouble than it was
worth, and it said the minimum number of control bits was 2, I preferred not
to go that way.
I've ended up using a mixture of FT_Stuff() and things from.AN2232C.
In fact, I have struggled with their documentation.
It seems odd to me that there is no place which brings together the process
of doing SPI (FT_SetBitMode() is not mentioned in AN2232C-01 Command
Processor for MPSSE and MCU Host Bus Emulation Modes). That document
mentions a SETUP command, mentioned nowhere else.
D2XX Programmer's Guide has FT_SetBitMode() but SPI is not mentioned (MPSSE
is) and SPI does not appear in the index either. And FT_GetBitMode() does
not get back the mode but the state of the data bus. And does
FT_ResetDevice() just do a FT_SetBitMode with a mode of zero (reset).
And at some point I have to change the descriptors to support full speed
mode.
And as for examples in Pascal - how quaint!
I am sure the technology is great, but using it is a bit of a challenge.
Rgds,
Bill
.
- Follow-Ups:
- Re: FTDI2232D & SPI
- From: ghelbig
- Re: FTDI2232D & SPI
- References:
- FTDI2232D & SPI
- From: Bill Davy
- Re: FTDI2232D & SPI
- From: The Real Andy
- FTDI2232D & SPI
- Prev by Date: Re: USB firmware programming
- Next by Date: Re: Data to fill into unused program space on ARM7.
- Previous by thread: Re: FTDI2232D & SPI
- Next by thread: Re: FTDI2232D & SPI
- Index(es):
Relevant Pages
|
