FPGA Intellectual Property
PCI Express*, Networking and Connectivity, Memory Interfaces, DSP IP, and Video IP
Announcements
Intel Support hours are Monday-Fridays, 8am-5pm PST, except Holidays. Thanks to our community members who provide support during our down time or before we get to your questions. We appreciate you!

Need Forum Guidance? Click here
Search our FPGA Knowledge Articles here.
5881 Discussions

Generic Serial Flash Interface for single SPI - how to connect MISO, MOSI?

xgiaime
Novice
565 Views

Hello,

 

I implemented the Generic Serial Flash Interface to connect to a W25Q80DVSSIG TR 8Mb serial flash. I would like to use simple SPI: so I have CLK, nCS, MISO and MOSI to connect.

 

The HDL generated shows:

board_flash_spi_qspi_pins_dclk              : out  std_logic;                    

board_flash_spi_qspi_pins_ncs              : out  std_logic;                    

board_flash_spi_qspi_pins_data              : inout std_logic_vector(3 downto 0) := (others => 'X');

 

Data is an "inout" type of 4 bits, which looks ok for Quad SPI. However I only have MISO and MOSI.

How to connect this? There's no explanations in the IP documentation.

How to set the interface mode (Quad, dual, single)? There's no option in the Platform Designer.

 

PS additional notes:

I'm using a MAX10 10M08SAU device, with Quartus 18.1, and I'm using VHDL language.

 

Thanks and best regards,

Giaime

0 Kudos
3 Replies
xgiaime
Novice
338 Views

No one to step in?

Thanks in advance and best regards

Giaime

YuanLi_S_Intel
Employee
338 Views

Hi Giaime Ugliano,

 

Sorry for the late. The IP supports Single, Dual and Quad mode. No setting is needed on the IP for Single, Dual and Quad mode. It is on the flash. If your flash support single, dual and quad mode, you will need to enable it on flash using Generic Serial Flash IP.

 

I just checked the flash datasheet, seems like it has 4 data I/O pin as well. You can just connect the 4 data I/O pin with the QSPI_PINS_Data.

 

Thank You

xgiaime
Novice
338 Views

Hello Bruce,

 

thank you very much for your reply!

The issue is, the PCB is already done connecting only MISO and MOSI to the FPGA. This is because the Flash itself defaults to single SPI mode, if you don't use the special instructions.

In this case, how do you think it's best to connect the pins? They're INOUT type, while my MISO is IN and MOSI is OUT types. How to handle that?

 

Thank you very much in advance,

best regards

Giaime

Reply