V9990 Central

Graphic Modes and Register Settings

Mode Display resolution
(Pixel Aspect Ratio)		 Bit depth Image sizes P#7 R#6 R#7
MCS

Master Clock Selection

  1. XTAL1 (21.5MHz)
  2. MCKIN (14.3MHz)
DSPM

Display Mode

  1. P1 mode
  2. P2 mode
  3. Bitmap mode
  4. Standby mode
DCKM

Dot Clock Mode

  1. MCS/4
  2. MCS/2
  3. MCS
XIMM

X Image Space Width

  1. 256
  2. 512
  3. 1024
  4. 2048
CLRM

Color Mode

  1. 2 bits/pixel
  2. 4 bits/pixel
  3. 8 bits/pixel
  4. 16 bits/pixel
C25M

Select 25MHz Master Clock

  1. P1, P2, B1~5 modes
  2. B6 mode
SM1 *

Number of vertical lines
when non-interlaced NTSC

  1. 262 lines
  2. 263 lines
SM †

Horizontal frequency

  1. 1H = MCS/228
  2. 1H = MCS/227.5
PAL ‡

PAL Mode

  1. NTSC specs for vertical frequency
  2. PAL specs for vertical frequency
EO ‡

Vertical Resolution
when interlaced

  1. Same as when non-interlaced
  2. Twice as when non-interlaced
IL ‡

Interlace Mode

  1. Non-interlaced
  2. Interlaced
HSCN

Horizontal High Scan Mode

  1. P1, P2, B1~4 modes
  2. B5, B6 modes
* B0 and B7 modes are undocumented
† B5 mode can't be used in most monitors
‡ B6 mode can't be used with current V9990 cards for MSX
 * When both SM1 and SM are set, subcarrier phase is inverted for each frame; invalid in B5 and B6 modes
† When SM is set, subcarrier phase is inverted for each line; invalid in B5 and B6 modes
‡ These settings are invalid in B5 and B6 modes
P1 256x212
(8:7 ≈ 1.14)		 4 512x512 0 0 0 1 1 0 0/1 0/1 0/1 0/1 0/1 0
P2 512x212
(4:7 ≈ 0.57)		 4 1024x512 0 1 1 2 1 0 0/1 0/1 0/1 0/1 0/1 0
B0 * 192x240
(12:7 ≈ 1.71)		 16, 8, 4, 2 256, 512,
1024, 2048		 1 2 0 0~3 0~3 0 0/1 0/1 0/1 0/1 0/1 0
B0 * 192x240
(12:7 ≈ 1.71)		 16 256x1024 1 2 0 0 3 0 0/1 0/1 0/1 0/1 0/1 0
512x512 1
1024x256 2
8 256x2048 0 2
512x1024 1
1024x512 2
2048x256 3
4 256x4096 0 1
512x2048 1
1024x1024 2
2048x512 3
2 256x8192 0 0
512x4096 1
1024x2048 2
2048x1024 3
B1 256x212
(8:7 ≈ 1.14)		 16, 8, 4, 2 256, 512,
1024, 2048		 0 2 0 0~3 0~3 0 0/1 0/1 0/1 0/1 0/1 0
B1 256x212
(8:7 ≈ 1.14)		 16 256x1024 0 2 0 0 3 0 0/1 0/1 0/1 0/1 0/1 0
512x512 1
1024x256 2
8 256x2048 0 2
512x1024 1
1024x512 2
2048x256 3
4 256x4096 0 1
512x2048 1
1024x1024 2
2048x512 3
2 256x8192 0 0
512x4096 1
1024x2048 2
2048x1024 3
B2 384x240
(6:7 ≈ 0.86)		 16, 8, 4, 2 512, 1024,
2048		 1 2 1 1~3 0~3 0 0/1 0/1 0/1 0/1 0/1 0
B2 384x240
(6:7 ≈ 0.86)		 16 512x512 1 2 1 1 3 0 0/1 0/1 0/1 0/1 0/1 0
1024x256 2
8 512x1024 1 2
1024x512 2
2048x256 3
4 512x2048 1 1
1024x1024 2
2048x512 3
2 512x4096 1 0
1024x2048 2
2048x1024 3
B3 512x212
(4:7 ≈ 0.57)		 16, 8, 4, 2 512, 1024,
2048		 0 2 1 1~3 0~3 0 0/1 0/1 0/1 0/1 0/1 0
B3 512x212
(4:7 ≈ 0.57)		 16 512x512 0 2 1 1 3 0 0/1 0/1 0/1 0/1 0/1 0
1024x256 2
8 512x1024 1 2
1024x512 2
2048x256 3
4 512x2048 1 1
1024x1024 2
2048x512 3
2 512x4096 1 0
1024x2048 2
2048x1024 3
B4 768x240
(3:7 ≈ 0.43)		 4, 2 1024, 2048 1 2 2 2~3 0~1 0 0/1 0/1 0/1 0/1 0/1 0
B4 768x240
(3:7 ≈ 0.43)		 4 1024x1024 1 2 2 2 1 0 0/1 0/1 0/1 0/1 0/1 0
2048x512 3
2 1024x2048 2 0
2048x1024 3
B5 † 640x400
(5:6? = 0.83?)		 4, 2 1024, 2048 0 2 2 2~3 0~1 0 0 0 0 0 0 1
B5 † 640x400
(6:5? = 1.2?)		 4 1024x1024 0 2 2 2 1 0 0 0 0 0 0 1
2048x512 3
2 1024x2048 2 0
2048x1024 3
B6 ‡ 640x480
(39:40? = 0.975?)		 4, 2 1024, 2048 0 2 2 2~3 0~1 1 0 0 0 0 0 1
B6 ‡ 640x480
(39:40? = 0.975?)		 4 1024x1024 0 2 2 2 1 1 0 0 0 0 0 1
2048x512 3
2 1024x2048 2 0
2048x1024 3
B7 * 1024x212
(2:7 ≈ 0.29)		 4, 2 1024, 2048 0 2 2 2~3 0~1 0 0/1 0/1 0/1 0/1 0/1 0
B7 * 1024x212
(2:7 ≈ 0.29)		 4 1024x1024 0 2 2 2 1 0 0/1 0/1 0/1 0/1 0/1 0
2048x512 3
2 1024x2048 2 0
2048x1024 3