[flashrom] SPI modes for FT4232 chip

[Stany MARCEL]

On Sun, Oct 17, 2010 at 10:48 AM, Stany MARCEL <stanypub at gmail.com> wrote:
> On Sat, Oct 16, 2010 at 2:20 PM, Stany MARCEL <stanypub at gmail.com> wrote:
>> Hello,
>>
>> I want to use the FT4232 or FT2232 (with libfti) as a SPI master.
>>
>> Thanks to you I have a good example of SPI code with libftdi and this
>> device since you added it to your supported flasher.
>>
>> I still don't know how to change some behavior of this component :
>>
>> - Clock mode
>> Mode 0:  CPOL= 0  CPHA=0
>> Mode 1:  CPOL= 0  CPHA=1
>> Mode 2:  CPOL= 1  CPHA=0
>> Mode 3:  CPOL= 1  CPHA=1
>>
>> - Data shift order, MSB or LSB First.
>>
>> If you have any information on theses subject, I'm very interested.
>>
>> Thanks in advance
>>
>>
>> Extract from FTDI Documentation :
>> For CPOL = 0, the base (inactive) level of SCLK is 0. In this mode:
>>  * When CPHA = 0, data will be read in on the rising edge of SCLK, and
>> data will be clocked out on the falling edge of SCLK.
>>  * When CPHA = 1, data will be read in on the falling edge of SCLK,
>> and data will clocked out on the rising edge of SCLK
>> For CPOL =1, the base (inactive) level of SCLK is 1. In this mode:
>>  * When CPHA = 0, data will be read in on the falling edge of SCLK,
>> and data will clocked out on the rising edge of SCLK
>>  * When CPHA =1, data will be read in on the rising edge of SCLK, and
>> data will be clocked out on the falling edge of SCLK.
>>
>
> I found the needed informations in the SPI dll given by ftdi and the
> ftdi.h from libftdi.h
>
> #define SPI_CMD_WR_BYTES_MSB_RE /* 0001 0000 */ (MPSSE_DO_WRITE)
> #define SPI_CMD_WR_BYTES_MSB_FE /* 0001 0001 */ (MPSSE_DO_WRITE|MPSSE_WRITE_NEG)
> #define SPI_CMD_WR_BYTES_LSB_RE /* 0001 1000 */ (MPSSE_DO_WRITE|MPSSE_LSB)
> #define SPI_CMD_WR_BYTES_LSB_FE /* 0001 1001 */
> (MPSSE_DO_WRITE|MPSSE_LSB|MPSSE_WRITE_NEG)
>
> #define SPI_CMD_RD_BYTES_MSB_RE /* 0010 0000 */ (MPSSE_DO_READ)
> #define SPI_CMD_RD_BYTES_MSB_FE /* 0010 0101 */
> (MPSSE_DO_READ|MPSSE_READ_NEG|MPSSE_WRITE_NEG)
> #define SPI_CMD_RD_BYTES_LSB_RE /* 0010 1000 */ (MPSSE_DO_READ|MPSSE_LSB)
> #define SPI_CMD_RD_BYTES_LSB_FE /* 0010 1101 */
> (MPSSE_DO_READ|MPSSE_LSB|MPSSE_READ_NEG|MPSSE_WRITE_NEG)
>
> I will test all theses modes with an oscilloscope to verify that it
> works as expected.
>

Hello,

I have posted the first results of my work :

http://code.google.com/p/libftdispi/

Regards,
-- 
Stany