Embedded Intel® Core™ Processors
Intel® Core™ Hardware, Software, Firmware, Graphics
1003 Discussions

CFL/PCH does not work after SLP_A#.


Hello. There.


I made my own board with COFFEE LAKE H.

If I had known the support page before, I would have requested circuit review or artwork review

First I made it based on my own datasheet.

I'll use the FPGA to directly adjust the PCH's power sequence.

While looking at the PDG document, I am writing the power sequence control in Verilog.

I am making a control program referring to the '45.4 Power Sequencing' item in the PDG document.

All of the VCCPRIM power is applied to the PCH, and both SLP_SUS# and SLP_A# come out normally. However, even after pressing the power button, SLP_S5# is always in assert state.

Of course it doesn't go to S4 and S3.

When I press PWRBTN for about 4 seconds, SLP_A# turns off and on, so PCH seems to work.

However, it does not work after S5#. 

Could it have something to do with the BIOS?

Both 'Figure 45-3' and 'Figure 45-4' in the '571391_CFL_H_PDG' document appear to access SPI FLASH after S5#.

I understood DSW_PWROK -> RSMRST -> PWRBTN -> S5#, but it stopped from S5#.

The assembled CPU is CL8068404165301S RFEJ and the PCH is FH82CM246 SR40E.

If the process does not work after SLP_A#, please review which part to check from.


0 Kudos
1 Reply

Hello, @lkk_vmetech:

Thank you for contacting Intel Embedded Community.

You need to verify that the affected design fulfills the SLP_A# requirements, which are stated in Tables 21-1, 33-5, 33-6, 33-8, 36-1, 45-1, and 45-5; in sections 33.5.1, 36.2.2, 36.2.7, 36.28, 36.2.19, and36.2.20, and; also in Figures 45-3 and 45-4, on pages 321, 378, 380, 381 425, 508, 522, 371, 426, 427, 429, , 513, and 515 of the Coffee Lake H Platform Design Guide (PDG) document # 571391. It can be found when you are logged into your Resource & Design Center (RDC) privileged account on the following website:


The RDC Account Support form is the channel to process your account update request or report any inconveniences with the provided site. It can be found at:


Best Regards,