HP INCFollow


There has more and more big size (> 21”) display monitor in the marketing, some of the

user might not put on horizontal (width > height) and will change to vertical (height >

width). We have some specific product also shipping with the monitor fixed on vertical

mode like cashier system.

In OS environment, user can through graphics driver to change the display setting, it can

rotate to the correct angle what user use and can be control by user.

In pre-OS environment, some of monitor mount with G-sensor, therefore BIOS can aware

current display is put as horizontal or vertical and output the display correctly, like the post

logo or BIOS setup or any other post message.

Some of unit would like to save the G-sensor cost and can use GPIO pin to achieve that,

but the limitation is that cannot be dynamitic change and need to lock down the mode

(Horizontal or Vertical) before the product shipping since it cannot be changed (like

cashier). This design only can apply on the unit that has fixed the monitor and cannot be


Without G-sensor or GPIO to report the correct mode, and user does not put the monitor

as normal use case therefore the screen during BIOS post cannot show up correctly, if

user would like to check post message or boot into setup mean that will be a big problem

for them.

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