W5500 MACRAW mode and Interrupt Pin

Question

I am using WIZ550io module in MACRAW mode and want the interrupt Pin to act when there is any actvity on socket 0. Precisely i would like WIZ550io to assert the INT pin low when an ethernet frame is received in the W5500 buffer, this would reduce my over head of scanning Sn_RX_RSR register and read the frame once the interrupt arrives. The data sheet doesn’t mention any thing about the interrupt pin to work in MACRAW mode and I tried setting the Interrupt Mask register and Socket Interrupt Mask registers, however i didnt see any activity on the INT Pin. I would like to know if the W5500 asserts INT pin even in MACRAW mode or Am I missing some setting of the registers.

Eugeny · Answer

This is very good question! Looking to the W5100 datasheet where you can see the driving algorithms, the chapter about MACRAW says that it is the same as UDP, but UDP may use interrupt for receiving. Thus I assume that if data is received, it should raise RECV bit of Sn_IR, and thus main interrupt signal. Please check your code against the W5100 datasheet (chapter 5) and let us know.

vipulpanch86 · Answer

Thanks Eugeny, I understood the problem, I was setting IMR and SIMR registers, however i missed out on setting Sn_IMR. Sn_IMR is zero by default, hence all the interrupts are masked out and it doesn’t signal SIR. I am able to get the required interrupts now.