EP0360243A2
Expired / Lapsed
EP
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Video memory device
Assignee: Toshiba Corp
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Filing: 1989-09-20
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Granted: —
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Expires: 2009-09-20
Abstract
Abstract A video memory device includes a RAM (2) and a plurality of SAMs (4A, 4B). RAM (2) is constructed of a plurality of memory cells disposed in a matrix. Data are transferred between a memory cell designated by an address and a RAM port. Each SAM (4A and 4B) is constructed as a multi-word length type and connected to each of a plurality of columns of RAM (2). Multi-bit data are transferred between each SAM (4A, 4B) and RAM (2), and are serially input/output via a plurality of SAM ports (8A, 8B).
Inventors
- 👤 Haruki Toda
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-30 05:10
CPC Classifications
G; G11; G11C; G11C7/00; G11C7/10; G11C7/1075; G11C7/1006; G11C8/00; G11C8/12; Y; Y02; Y02E; Y02E10/00; Y02E10/50
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
175 words
A video memory device comprising a RAM (2) and a plurality of SAMs (4A, 4B), wherein said RAM (2) is constructed of a plurality of memory cells disposed in a matrix having a plurality of rows and columns, one of said memory cells being selected through designation by row and column addresses, and one bit data being transmitted between said selected memory cell and a RAM port (8), and said one bit data is input/output to/from the RAM port (8); and wherein each of said SAMs (4A and 4B) is constructed as a multi-word length type and connected to a plurality of columns of said RAM (2), and each of said SAMs transmitting/receiving data to/from said memory cells belonging to said columns connected to said each of said SAMs (4A and 4B), and each of said SAMs inputting/outputting data to/from via a plurality of SAM ports (8A, 8B), whereby the data in said RAM (2) are input/output as multi-bit data via said plurality of SAM ports (8A, 8B) of said plurality of SAMs (4A, 4B).
Claim 2
Dependent Claim
175 words
A video memory device comprising a RAM (2) and a plurality of SAMs (4A, 4B), wherein said RAM (2) is constructed of a plurality of memory cells disposed in a matrix having a plurality of rows and columns, one of said memory cells being selected through designation by row and column addresses, and one bit data being transmitted between said selected memory cell and a RAM port (8), and said one bit data is input/output to/from the RAM port (8); and wherein each of said SAMs (4A and 4B) is constructed as a multi-word length type and connected to a plurality of columns of said RAM (2), and each of said SAMs transmitting/receiving data to/from said memory cells belonging to said columns connected to said each of said SAMs (4A and 4B), and each of said SAMs inputting/outputting data to/from via a plurality of SAM ports (8A, 8B), whereby the data in said RAM (2) are input/output as multi-bit data via said plurality of SAM ports (8A, 8B) of said plurality of SAMs (4A, 4B).
Claim 3
Dependent Claim
24 words
A video memory device according to claim 1, wherein each of said plurality of columns is connected to one of said SAMs (4A, 4B).
Claim 4
Dependent Claim
25 words
A video memory device according to claim 1, wherein each of said plurality of columns is multiple-connected to a plurality of said SAMs (4A, 4B).
Claim 5
Dependent Claim
80 words
A video memory device according to claim 1, wherein each of said SAMs (4A, 4B) is divided into first and second groups, the first group being accessed during the first half of a serial access time of said SAMs and the second group being accessed during the second half of said serial access time, and while one of said first and second groups serially outputs/inputs data, the other of said first and second groups transmits/receives data to/from said RAM (2).
Claim 6
Dependent Claim
35 words
A video memory device according to claim 1, wherein each of said plurality of SAMs (4A, 4B) is made capable of being set at one of serial input and output modes, independently of each other.
Claim 7
Dependent Claim
35 words
A video memory device according to claim 4, wherein each of said plurality of SAMs (4A, 4B) is made capable of being set at one of serial input and output modes, independently of each other.
Claim 8
Dependent Claim
51 words
A video memory device according to claim 1, wherein each of said plurality of SAMs (4A, 4B) is made capable of being set with a serial cycle time independently of each other, and each of said SAMs (4A, 4B) is made capable of being set with a serial cycle time asynchronously.
Claim 9
Dependent Claim
33 words
A video memory device according to claim 4, wherein said first and second groups are alternately connected via split selectors (6A, 6B) to said SAM ports (8A, 8B) for the serial data input/output.
Claim 10
Dependent Claim
33 words
A video memory device according to claim 6, wherein said first and second groups are alternately connected to said SAM ports (8A, 8B) by split selectors (6A, 6B) for the serial data input/output.
References Cited (Backward Citations)
No citation records indexed.
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