[flashrom] SPI modes for FT4232 chip

[Carl-Daniel Hailfinger]

On 23.10.2010 01:29, Stany MARCEL wrote:
> 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.
>>     
> I have posted the first results of my work :
>
> http://code.google.com/p/libftdispi/
>   

Nice. Maybe you want to tell the libftdi authors about your project as
well. They like to know who is using their library.

Regards,
Carl-Daniel

-- 
http://www.hailfinger.org/