From 5aaca8a160acb4d8d8dc60d185414b284e9d26a1 Mon Sep 17 00:00:00 2001
From: Albert Liu <45282415+ggrtk@users.noreply.github.com>
Date: Fri, 25 Sep 2020 19:26:02 -0700
Subject: [PATCH] Add note on GP0(02h) height masking

---
 graphicsprocessingunitgpu.md | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/graphicsprocessingunitgpu.md b/graphicsprocessingunitgpu.md
index acaff8d..7a648bb 100644
--- a/graphicsprocessingunitgpu.md
+++ b/graphicsprocessingunitgpu.md
@@ -502,6 +502,8 @@ Fill does NOT occur when Xsiz=0 or Ysiz=0 (unlike as for Copy commands).
 Xsiz=400h works only indirectly: Param=400h is handled as Xsiz=0, however,
 Param=3F1h..3FFh is rounded-up and handled as Xsiz=400h.<br/>
 
+Note that because of the height (Ysiz) masking, a maximum of 511 rows can be filled in a single command. Calling a fill with a full VRAM height of 512 rows will be ineffective as the height will be masked to 0.
+
 #### Masking for COPY Commands parameters
 ```
   Xpos=(Xpos AND 3FFh)                       ;range 0..3FFh