AMD Geodeā„¢ LX Processors Data Book 447
Video Processor Register Descriptions 33234H
6.8.3.35 Video Request (VRR)
16 ALPHA3_WIN_
EN
Alpha Window 3 Enable. Enable bit for alpha window 3.
0: Disable alpha window 3.
1: Enable alpha window 3.
15:8 ALPHA3_INC Alpha Window 3 Increment. Specifies the alpha value increment/decrement. This is a
signed 8-bit value that is added to the alpha value for each frame. The MSB (bit 15) indi-
cates the sign (i.e., increment or decrement). When this value reaches either the maxi-
mum or the minimum alpha value (255 or 0) it keeps that value (i.e., it is not incremented/
decremented) until it is reloaded via LOAD_ALPHA (bit 17).
7:0 ALPHA3_MUL Alpha Window 3 Value. Specifies the alpha value to be used for this window.
VP Memory Offset 120h
Type R/W
Reset Value 00000000_001B0017h
A3T Bit Descriptions (Continued)
Bit Name Description
VRR Register Map
63 62 61 60 59 58 57 56 55 54 53 52 51 50 49 48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33 32
RSVD
313029282726252423222120191817161514131211109876543210
RSVD XRQ RSVD YRQ
VRR Bit Descriptions
Bit Name Description
63:28 RSVD (RO) Reserved (Read Only). Reads back as 0.
27:16 XRQ Video X Request. Indicates the horizontal (pixel) location to start requesting video data
from.
15:11 RSVD (RO) Reserved (Read Only). Reads back as 0.
10:0 YRQ Video Y Request. Indicates the line number to start requesting video data from.