# ULPM boot on GPIO 38 &39

**URL:** <https://mangoh.discourse.group/t/ulpm-boot-on-gpio-38-39/1258>\
**Category:** mangOH Green\
**Created:** [March 20, 2018, 2:47pm UTC](https://mangoh.discourse.group/t/ulpm-boot-on-gpio-38-39/1258 "2018-03-20T14:47:13Z")\
**Posts on this page:** 1\
**Showing post:** 4

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**Author:** ![mrjoso](https://avatars.discourse-cdn.com/v4/letter/m/9e8a1a/32.png) [@mrjoso](https://mangoh.discourse.group/u/mrjoso)\
**Post date:** [March 23, 2018, 7:37pm UTC](https://mangoh.discourse.group/t/ulpm-boot-on-gpio-38-39/1258/4 "2018-03-23T19:37:38Z")

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Hi Johnn,  
waking up WP7502 with GPIO38 from ULPM works on my Red board.  
I use le\_ulpm\_BootOnGpio() inside my app.  
But I’m convinced that there is a bug which disables to wake up the chip from suspend mode, and ChangeEventHandler does not work.  
More info [in this thread.](https://mangoh.discourse.group/t/wake-up-from-suspend-mode-on-gpio-interrupt/720)

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