Configure EVT0_B, EVT1_B, EVT2_B, EVT3_B and EVT4_B as input pin on LS1043

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Configure EVT0_B, EVT1_B, EVT2_B, EVT3_B and EVT4_B as input pin on LS1043

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bhargavjayswal
Contributor III

Currently I have utilize all interface and pin available on LS1043 and I require to have an extra GPIO to identify my board version. By reviewing schematic of LS1043ARDB , I find that EVT0 to EVT4 pins are pull up with 4.7K register and not used at anywhere.

In technical reference manual of LS1043, Appendix C represent EPU register descriptions. Where EPU base address is 2000_0000h. 

EVT0_ADDR -> 2000_0000 + (50h + (0 x 4h)) = 2000_0050     (EPEVTCR0)

EVT1_ADDR -> 2000_0000 + (50h + (1 x 4h)) = 2000_0054     (EPEVTCR1)

EVT2_ADDR -> 2000_0000 + (50h + (2 x 4h)) = 2000_0058     (EPEVTCR2)

EVT3_ADDR -> 2000_0000 + (50h + (3 x 4h)) = 2000_005C    (EPEVTCR3)

EVT4_ADDR -> 2000_0000 + (50h + (4 x 4h)) = 2000_0060     (EPEVTCR4)

 

So if I configure 0th bit DIR as 0b then it will configure as input pin then I can read status of that pin from EPRSRSVn.

As per my understating if ENTn_B pin is configure with external pull-up then I will get value 1 from EPRSRSVn register.if ENTn_B pin configure with external pull-down then i will get value 0 from EPRSRSVn register.

 

Request you to confirm this, please let me know for any improvement or changes.

 

Regards,

Bhargav Jayswal

 

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2 Replies

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SebastianG
NXP TechSupport
NXP TechSupport

Hi @bhargavjayswal,

This configuration seems good 

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bhargavjayswal
Contributor III

Thanks for  update.

 

Now based  on above configuration, can we use this pin as an input gpio during u-boot to validate state of the pin whether is high or low? 

 

Regards,

Bhargav Jayswal

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