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is a Display Controller Integrated Circuit. offering considerable advantages to the Amiga product line, both new features and higher performance.

The basic function of Lisa is to accept bitplane data and sprite data from chip ram, and serialize and prioritize them to provide a set of signals suitable for input to a video DAC. Lisa also provides mouse/joystick circuitry and genlock support.

Lisa (von HP)

New features for Lisa (as compared to ECS Denise):

  • 32 bit wide data bus supports input of 32-bit wide bitplane data and allows doubling of memory bandwidth. Additional doubling of bandwidth can be achieved by using Fast Page Mode Ram. The same bandwidth enhancements are available for sprites. Also the maximum number of bitplanes useable in all modes was increased to eight (8).
  • The Color Palette has been expanded to 256 colors deep and 25 bits wide(8 RED,8 GREEN,8 BLUE,1 GENLOCK). This permits display of 256 simultaneous colors in all resolutions. A palette of 16,777,220 colors is available in all resolutions.
  • 28Mhz clock input allows for cleaner definition of HIRES and SHRES pixels. ALICE's clock generator is synchronized by means of LISA's 14MHz and SCLK outputs. Genlock XCLK and XCLKEN* pins have been eliminated (external MUX is now required) .
  • A new register bit allows sprites to appear in the screen border regions.
  • A bitplane mask field of 8 bits allows an address offset into the color palette. Two 4-bit mask fields do the same for odd and even sprites.
  • In Dual Playfield modes, 2 4~bitplane playfields are now possible in all resolutions.
  • Two extra high-order playfield scroll bits allow seamless scrolling of up to 64 bit wide bitplanes in all resolutions. Resolution of bitplane scroll, display window, and horizontal sprite position has been improved to 3Sns in all resolutions.
  • A new 8 bitplane HAM mode has been created, 6 for colors and 2 for control bits. Both HAM modes are available in all resolutions (not just LORES as before).
  • A RST input pin has been added, which resets all the bits contained in registers that were new for ECS or LISA: BPLCON3, BPLCON4, CLXCON2, DIWHIGH, FMODE.
  • Hardware Scan Doubling support has been added (modified SPRxPOS SH1O bit definition).

LISA Chip Elements:

  • 256 Color Registers
  • 8 64-bit Bitplane Shift Registers
  • Bitplane Priority and Control Registers
  • Color Select Decoder
  • Priority Control Logic
  • 8 Sprite Serial Lines
  • 8 64-bit Sprite Shift Registers (2 planes wide)
  • 16 bit Serial Mouse/Joystick/Configuration Port
  • Sprite Position Compare Logic
  • Sprite Horizontal Control Registers
  • Collision Detect Logic.
  • Collision Control Register.
  • Collision Storage Register.
  • Buffer - Data Bus.
  • Buffer - Register Address Decode.
  • Full 25 Bit Digital Video Port

Extended description of signals and registers are stored in the Commodore specification for Lisa (see below).

in the Amiga

TypCommo-No. C= Description C= Info Form Editors Info
A 391227-01IC 4203 VLSI VID.DISPAMIGA-1200/4000PLCC84
Lisa (von CBM)
atCountTypPosition Notice
A1200 1 A U4,-
A4000 1 A U450,-
A4000-T 1 A U450,-
CD-32 1 A U4,-

from: CBM und HP


1VSS0 (GND) 29B0 57R7
2D6 30VDD0 (+5V) 58_BURST
3D5 31B1 59D31
4D4 32B2 60D30
5D3 33VSS1 (GND) 61D29
6D2 34B3 62D28
7D1 35B4 63D27
8D0 36B5 64D26
9_CAS 37B6 65D25
10CCK 38B7 66D24
11WIDE 39G0 67D23
12RGA8 40G1 68D22
13RGA7 41G2 69D21
14RGA6 42G3 70D20
15RGA5 43C28Out 71D19
16RGA4 44G4 72D18
17RGA3 45G5 73D17
18RGA2 46G6 74D16
19RGA1 47G7 75D15
20MDAT 48R0 76D14
21_MLD 49R1 77D13
22SCLK 50R2 78D12
23C14O 51R3 79D11
24_RST 52R4 80D10
25C28M 53VSS2 (GND) 81D9
26SOG 54R5 82D8
27BLANK 55R6 83VDD2 (+5V)
28ZD 56VDD1 (+5V) 84D7

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Last modified: 2018/08/05 19:17