Devices, systems and methods for palette pass-through mode

A computer graphics system for use with a host computer that produces first color code signals according to a first graphics standard, comprising:

• a printed wiring board having first and second physically separate connectors;
• a graphics processor mounted on the printed wiring board and connected to the firs connector for communication with the host computer;
• a video memory mounted on the printed wiring board and connected to said graphics processor to produce second color code signals according to a second graphics standard;
• and
• a palette device mounted on the printed wiring board and connected to the video memory by printed wiring, said palette device comprising:
• an input register with a first register section connected to said video memory to enter a first set of color code bits according to the second graphics standard and a second register section connected to said second connector of said printed wiring board to enter a second set of color code bits form the host computer according to the first graphics standard;
• a look-up table memory for supplying color data words in response to color codes;
• a selector circuit connected between said input register and said look-up table memory, the selector circuit controllable by said graphics processor to select one of the first or second graphics standard and to transfer corresponding first or second color codes bits from said input register according to the selected first or second graphics standard to said look-up table memory.

A computer system comprising:

• a host computer having a mother board and a microcomputer chip and memory chips mounted thereon;
• a first printed wiring board attached to said mother board and having graphics circuitry mounted thereon and producing first color code signals according to a first graphics standard, said first printed wiring board attached to said motherboard for control of said graphics circuitry by said microcomputer chip, and said first printed wiring board having a feature connector for output of said first color code signals according to the first graphics standard;
• a second printed wiring board attached to said mother board and having a graphics processor mounted thereon and responsive to control by said microcomputer chip, and a video memory mounted on the second printed wiring board and connected to said graphics processor to produce second color code signals according to a second graphics standard, and said second printed wiring board having a feature connector connected to said feature connector of said first printed wiring board for input to said second printed wiring board of first color code signals according to the first graphics standard;
• and
• a palette device mounted on the second printed wiring board and connected to the video memory by printed wiring, said palette device comprising:
• an input register with a first area connected to said video memory via printed wires of said second printed wiring board to enter a first set of color code bits according to the second graphics standard and a second area connected to said feature connector of said second printed wiring board to enter a second set of color code bits according to the first graphics standard;
• a look-up table memory for supplying color data words in response to color codes;
• a selector circuit connected between said input register and said look-up table memory, the selector circuit controllable by said graphics processor to select one of the first or second graphics standard and to transfer corresponding first or second color code bits from said input register according to the selected first or second graphics standard to said look-up table memory.

A computer graphics system for use with a digital computer, comprising:

• a video memory having an input for connection to the digital computer rand operable to store color codes for graphics information;
• and
• a palette device including an input for respective bits representing color codes from a first graphics standard from a first graphics bus and a second set of bits from the video memory representing color codes from a second graphics bus;
• a look-up table memory for supplying color data words in response to color codes;
• a selector circuit connected between said input of said palette device and said look-up table memory, the selector circuit controllable by said digital computer to select one of the first or second graphics standard and to transfer color codes from the selected first or second graphics bus to said look-up table memory, the selector circuit further having inputs for a first video control signal from said digital computer and for a second video control signal so that said selector circuit selects a corresponding video control signal for output depending on the selected first or second graphics bus.

A printer system comprising:

• a digital computer operable to generate digital information according to a first graphics standard;
• a graphics coprocessor for said digital computer operable in response to said digital computer to generate digital information according to a second graphics standard;
• a video memory having an input for connection to the graphics coprocessor and operable to store color codes for graphics information;
• a palette device including
• an input register for holding respective bits form separate sets of input lines including a first set of input lines connected to said digital computer for signals representing color codes according to the first graphics standard and a second set of input lines connected to said video memory for signals from the video memory representing color codes according to the second graphics standard;
• a look-up table memory for supplying color data words in response to color codes;
• a selector circuit connected between said input register and said look-up table memory, the selector circuit controllable by said graphics coprocessor to select one of the first or second graphics standard and to transfer color codes according to the selected first or second graphics standard from said input register to said look-up table memory;
• and the printer system further comprising a color display connected to said palette device and a color printer assembly responsive to said digital computer to make a print of an image with color information generally corresponding to a corresponding image displayed on the color display.

A palette device for use with a digital computer that produces a first video control signal and first color code signals on a first graphics bus, the digital computer having circuitry that produces a different second video control signal and second color code signals on a second graphics bus, said palette device comprising:

• an input for a first set of bits representing first color codes from the first graphics bus and a second set off bits representing second color codes from the second graphics bus;
• a color data circuit for supplying color data words in response to color codes;
• a selector circuit connected between said input and said color data circuit, the selector circuit controllable to transfer color codes from a selected one of the first or second graphics bus to said color data circuit;
• and
• a graphics control circuit connected to said selector circuit to dynamically change the selection between the first and second graphics bus so that said color data circuit supplies color data words for an image to be displayed that includes color data words resulting from selection of the first and second graphics bus within a single frame of the same image.

A computer graphics system comprising:

• a digital computer that produces a first video control signal and first color code signals on a first graphics bus, the digital computer having circuitry that produces a different second video control signal second color code signals on a second graphics bus;
• and
• a palette device including:
• an input for a first set of bits representing first color codes from the first graphics bus and a second set of bits representing second color codes from the second graphics bus;
• a color data circuit for supplying color data words in response to color codes;
• a selector circuit connected between said input and said color data circuit, the selector circuit controllable to transfer color codes from a selected one of the first or second graphics bus to said color data circuit;
• a graphics control circuit connected to said selector circuit to dynamically change the selection between the first and second graphics bus so that said color data circuit supplies color data words for an image to be displayed that includes color data words resulting from selection of the first and second graphics bus within a single frame of the same image.