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--- doc:appunti:hardware:mini_pc_intel_pentium_j3710 [2026/02/23 16:07] – [Blanking the Virtual Terminal] niccolo
+++ doc:appunti:hardware:mini_pc_intel_pentium_j3710 [2026/02/24 19:12] (current) – [DPMS (Display Power Management Signaling)] niccolo
@@ Line 100: / Line 100: @@
 </code>
+==== DPMS (Display Power Management Signaling) ====
-FIXME What is this?
+DPMS (Display Power Management Signaling) is a VESA standard used to reduce monitor power consumption by controlling power states (On, Standby, Suspend, Off) generally based on user inactivity.
+It is possible to control the status of the display connected to the frame buffer writing some values to the pseudo file:
 <code>
@@ Line 108: / Line 111: @@
 </code>
-Writing the value 4 to the pseudodevice changes the **DPMS** property from **On=0** to **Off=3**. It is possibile to check all the properties using modeset
+| 0  | FB_BLANK_UNBLANK  | Screen ON (normal operation)  |
+| 1  | FB_BLANK_NORMAL  | Blank screen (no power saving)  |
+| 2  | FB_BLANK_VSYNC_SUSPEND  | Suspend vertical sync  |
+| 3  | FB_BLANK_HSYNC_SUSPEND  | Suspend horizontal sync  |
+| 4  | FB_BLANK_POWERDOWN  | Power down display (DPMS off)  |
-<code>
+Writing the value 4 to the pseudodevice changes the **DPMS** property from **On=0** to **Off=3**. It is possibile to check all the **connectors properties** using **modetest** (provided by the **libdrm-tests** Debian package):
+<code>
+modetest -M i915 -c
+opened device `Intel Graphics` on driver `i915` (version 1.6.0 at 20201103)
 Connectors:
 id      encoder status          name            size (mm)       modes   encoders
@@ Line 124: / Line 134: @@
         enums: On=0 Standby=1 Suspend=2 Off=3
         value: 3
+    ....
+     106     connected       HDMI-A-2        470x260         30      106
+  modes:
+        index name refresh (Hz) hdisp hss hse htot vdisp vss vse vtot
+  #0 1024x600 59.82 1024 1068 1156 1344 600 603 609 625 50250 flags: phsync, nvsync; type: preferred, driver
+  #1 1920x1080 60.00 1920 2008 2052 2200 1080 1084 1089 1125 148500 flags: phsync, pvsync; type: driver
+  ...
+DPMS:
+        flags: enum
+        enums: On=0 Standby=1 Suspend=2 Off=3
+        value: 3
+    ....
 </code>
+FIXME What is this?
 <code>
@@ Line 133: / Line 157: @@
 </code>
-The Debian package **libdrm-tests** contains the **modetest** tool.
 ===== Pygame =====