diff options
| author | James Cameron <quozl@laptop.org> | 2015-01-16 11:17:02 +1100 |
|---|---|---|
| committer | Mitch Bradley <wmb@firmworks.com> | 2019-11-08 07:38:30 -1000 |
| commit | 3ce738dc42c1cde4ab72d4977871bdb63b192095 (patch) | |
| tree | b55cc2c8e040909ca1432b3574582619dc70e858 | |
| parent | 562dfb9a098fe4536167b930e33b24973674b0d0 (diff) | |
| download | cforth-3ce738dc42c1cde4ab72d4977871bdb63b192095.tar.gz | |
OLPC XO-4 - lower display brightness
Lower the initial brightness from 15 to 10. This applies to the period
between CForth start and Open Firmware opening the display device.
Rationale:
New display backlight LEDs are to enter production for XO-4.
These make display brighter; 169 cd/m², with DCON brightness register at
maximum, at the Sugar home view.
We keep the perceived brightness the same as before (125 cd/m² same test
conditions), but allow the user to raise the brightness above the
previous maximum. We also lose some level of control in the range
downwards.
A manufacturing tag BL will identify units with new display backlight,
but access to tags in CForth is (by design) very simple and not yet
worth complicating.
Intent - new firmware with new display will show constant brightness
from turn on until Linux booted, consistent with the full brightness of
the original design.
Side effect - new firmware with old display will show brief (2s) low
brightness followed by normal brightness once Open Firmware sees no BL
tag.
See #12854.
| -rw-r--r-- | src/app/arm-xo-1.75/mmp2dcon.fth | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/src/app/arm-xo-1.75/mmp2dcon.fth b/src/app/arm-xo-1.75/mmp2dcon.fth index 46f8633..e0a8866 100644 --- a/src/app/arm-xo-1.75/mmp2dcon.fth +++ b/src/app/arm-xo-1.75/mmp2dcon.fth @@ -168,7 +168,7 @@ d# 905 value resumeline \ Configurable; should be set from args : dcon-enable ( -- ) dcon-setup true set-color - h# f bright! + h# a bright! ; : video-save |