Picture display memory system

• US 4,773,026 A
• Filed: 09/26/1984
• Issued: 09/20/1988
• Est. Priority Date: 09/26/1983
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Edamura, Atsuki, Ikeda, Tetsuya, Okamoto, Teiji, Takahara, Yasuaki
• Primary Examiner(s): Gruber, Felix D.
• Application Number:
  US06/654,461
• Time in Patent Office: 1,455 Days
• Field of Search: 364/518, 340/717, 340/747, 340/750, 340/798-800, 358/21 R
• US Class Current: 345/533
• CPC Class Codes: G06F 12/0207 with multidimensional access, e.g. row/column, matrix
• CPC Class Codes: G09G 5/022 using memory planes
• CPC Class Codes: G09G 5/393 Arrangements for updating the contents of the bit-mapped memory

Abstract

A picture display memory system with structure for changing over an address selection signal and data input signal fed to a picture memory depending upon whether the picture information is consecutive in the depth direction or is consecutive in the horizontal direction. When the picture information in the depth direction is to be written, the address selection signal is supplied to the picture memory to select a particular bit in the horizontal direction of the picture memory as an address, and the picture information of the depth direction is written into memory as a data input. When the picture information in the horizontal direction is to be written, bits in the horizontal direction are selected in accordance with the data contents of the picture pattern in the horizontal direction, and data stored in a register which stored beforehand the picture information of the depth direction is written into memory as a data input.

Claims

1. A picture display memory system comprising:

a central processing unit;

memory means, coupled via an address signal line and a data signal line to said central processing unit, and having m storage devices for storing color picture information for m picture elements, each of each storage devices having a plurality of storage areas for storing respective ones of l bits in commonly addressable storage locations;

picture information hold means for temporarily holding color picture information to be written into the storage locations of said memory means;

write control means activated in response to said central processing unit for carrying out successive operations of writing data into said memory means a predetermined number n times;

counter means presettable by said central processing unit to an address of data to be written in said memory means for supplying a write address to said memory means;

address update means for updating by m said address held in said counter means each time data is written into said memory means under control of said write control means; and

control information hold means for receiving from said central processing unit and holding n by m bits of control information at least during a period lasting from the time when said write control means is activated until n successive write operations to said memory means have been completed, and for supplying said information of n by m bits as selection signals to said storage devices of said memory means, so that said information held in said picture information hold means is written into said memory means or not depending upon said information held in said control information hold means in each of n write operations carried out by said write control means.

2. A picture display memory system according to claim 1, wherein said picture information hold means is connected to receive and hold color picture information comprising l bits, and said control information hold means is connected to the storage devices of said memory means for controlling writing of said held color information into those storage devices of said memory means selected by the control information held in said control information hold means and in storage locations of the selected storage devices designated by addresses based on the contents of said counter means.

3. A picture display memory system according to claim 2, wherein said counter means comprises a presettable counter coupled between said central processing unit and said memory means, and said address update means comprises a timing pulse generator for providing write timing pulses to said presettable counter so that the address held in said presettable counter is increased by m every time a write timing pulse is supplied from a timing pulse generator thereto, and further comprising switching means responsive to a data selection signal fed from said write control means for selecting m bits among the n by m bits of control information from said control information hold means to generate a selection signal for controlling writing of color information into said memory means, said switching means being connected between said control information hold means and said memory means.

4. A picture display memory system according to claim 3, further comprising:

memory selection signal generation means for generating a memory selection signal to select a particular one of said m storage devices of said memory means in accordance with an address signal received from said central processing unit via said address signal line;

memory selection changeover means for selecting either the memory selection signal fed from said memory selection signal generation means or the data signal fed from the central processing unit which has been held in said control information hold means, and for supplying the selected signal to storage device selection signal inputs of said memory means;

data input switching means for selecting either a data signal fed from said color picture information hold means or a data signal fed from said central processing unit and for supplying the selected signal to data inputs of said memory means; and

write mode setting means for storing a signal indicating either a first mode in which data is written into one storage device of said memory means or a second mode in which data is simultaneously written into a plurality of storage devices of said memory means, and for generating a signal for switching said memory selection switching means and said data input switching means in accordance with the stored mode indicating signal.

5. A picture display memory system comprising:

a central processing unit;

a memory coupled via an address signal line and a data signal line to said central processing unit, said memory having m storage devices for storing picture information, each of said storage devices having at least one addressable storage location of l bits;

memory selection signal generation means for generating a first memory selection signal in response to an address signal fed from said central processing unit via said address signal line, said memory selection signal being used to select a particular one of said m storage devices of said memory;

selection switching means connected to said data signal line and said memory selection signal generation means for selecting either said first memory selection signal received from said memory selection signal generation means or a data signal forming a second memory selection signal received from said central processing unit and for supplying the selected first or second memory selection signal to storage device selection signal inputs of said memory;

data hold means for holding l-bit data to be written into said memory;

data input switching means connected to said data signal line and said data hold means for selecting either the data signal fed from said data hold means or an l-bit data signal fed from said central processing unit and for supplying the selected data signal to data inputs of said memory;

write mode control means for storing a signal indicating either a first mode in which data is written into one storage device of said memory or a second mode in which data is simultaneously written into a plurality of storage devices of said memory and for controlling the operation of said selection switching means and said data input switching means in accordance with the mode indicating signal stored therein, so that said memory selection signal fed from said memory selection signal generation means and said data signal fed from the central processing unit are supplied respectively to memory selection inputs and data inputs of data memory when a signal indicating said first mode is stored in said write mode control means, and so that a memory selection signal fed from said central processing unit and said picture information held in said data hold means is supplied respectively to said memory storage device selection signal inputs and said data inputs of said memory when a signal indicating said second mode is stored in said write mode control means.