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IFONFIG register exchange | Cypress Semiconductor

IFONFIG register exchange

Summary: 4 Replies, Latest post by ruan hang on 27 Feb 2016 05:14 AM PST
Verified Answers: 0
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user_55294358's picture
186 posts



I trying to change operation mode from port mode to slave fifo mode.


When i power on, fx2lp is port mode then that's change to slave fifo mode by FPGA's triger.


Can i just only change IFCONFIG register value? I'm not sure whether or not.


But i dont know exactly exception problem.

So i want to know IFONFIG register exchange from port mode to slave fifo mode  F/W examples.




NIKL's picture
Cypress Employee
283 posts


Your question is not clear.
Do you mean to ask: Is changing the IFCONFIG enough to change the mode from PIO to Slave FIFO mode?

For switching the mode, you need to change IFCONFIG. Apart from that, you will have to take care to auto/manual config of EPFIFO buffers and whether the gpios used in PIO mode coincide with data bus or other lines used in Slave FIFO mode.


user_55294358's picture
186 posts

 I mean that if i wnat to change IFCONFIG from PIO mode to slave fifo mode during operation, is this can possible apply? Just i do change IFCONFIG register value during other operating?

gaya's picture
Cypress Employee
578 posts



You can change from the port IO mode to the slave fifo mode dynamically. However, whil doing so, you must take care of teh connections and other pin configurations. In port IO mode, all the portpins act as normal GPIOs. However, they have specific functionalities in the slave fifo mode, which can be found fro the TRM. While in slave fifo mode, all the interface connections should be properly done to ensure proper working. For example, say If an external IFCLK is chosen, it must be free-running at a minimum frequency of 5 MHz. In addition, in order to provide synchronization for the internal endpoint FIFO logic, the external IFCLK source must be present before the firmware sets IFCONFIG.7 = 0.




ruan hang's picture
2 posts

I want to choose an external clock,So I have set IFCONFIG.7 = 0 and the frequency of the IFCLK is 48MHz. Though it dosen't work .But when the ifclk is from the fx2lp,it works well. Why?

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