JPS58107590A - Display unit - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] (1) Technical field of the invention This invention 1! Method A relates to a display device using a pit pattern memory, and is intended to cut out only an arbitrary area of the pit pattern memory when displaying a mixture of characters and graphics.

(To display the background characters of sword technology, a character code is normally given to a character generator and a two-dimensional character pattern is generated from there.On the other hand, to display a figure, a memory called a bit pattern memory is stored in advance.) The required graphic pattern must be stored two-dimensionally.Storage graphic and display devices generally have both functions.

(5) Prior art and problems By the way, when displaying a mixture of characters and graphics in a nine-storage display device that uses a conventional pit pattern memory, the character mode and graphics mode must be switched or displayed in an overlapping manner. It is not possible to display figure y# only in one part of the screen. Furthermore, since the conventional device requires pit pattern memory for the screen size, it has the disadvantage of requiring a huge memory capacity.

(4) Issue l1111q) Purpose The present invention makes it possible to display arbitrary partial data of a pit pattern memory in an arbitrary area of a display screen, and also makes it possible for the memory not to have the capacity of one screen. be.

(5) Configuration of the Invention The display device of the unexploited sn specifies an arbitrary data area on the pit pattern memory that stores graphic data, and also specifies an arbitrary data area on the screen that prohibits the display of character patterns generated from a character generator. 1i'' is characterized in that a window area is designated and graphic data drawn out from the data area is displayed in the window area.

(6) Embodiments of the invention Hereinafter, the misfire will be explained in detail with reference to the illustrated embodiments.
explain. It is a professional diagram showing an example of the i11 diagram. Of these, the screen page and file 1 for storing character codes
, L812 for character display that extracts character codes line by line from the core P, F, character generator 3 that generates a character pattern corresponding to the given character code, converts the character pattern generated by the armpit generator into a raster for display The shift register 4 that also appears is a structure included in a normal character display device. Also, an mXm pit pattern memory 8 for storing graphic data, a register 9 for specifying the 70Y address, a register 10 for specifying the x address, a shift register 11 for shifting the data extracted from the memory 8, is a configuration included in ordinary storage type graphics and display devices. These share the display monitor 7 through the OR circuit 6.

5.12, location register 13. Bi, Toha turn read register 14,
A timing generation circuit 151 is added.

The case register 13 is a window area 7&t which prohibits character display from the entire screen of the display monitor 7 shown in FIG.
-It is specified by its character display address (row, column),
The starting address is (Rs, Cm) iSS child address (R1
, Cm). Note that %7a is an area where a character pattern is displayed. The bit pattern read register 14 is used to specify an arbitrary data area 8 in which graphic data to be displayed is stored from the entire area of the bit pattern /%'J8 shown in FIG.

The start address is (ΔX m , ΔYs), and the end address is (Δxm, ΔYm). Figure 2 is a time chart, where vR is a vertical synchronization signal, HRfl horizontal synchronization signal, and CCL.
K is character black, evening, RC is row counter, CC is column color y
This is a switching signal that exclusively controls the gates 5 and 121. 9 In Figure 1, CK is the basic clock, 8
H1 and 8Hs are shift clocks.

The tie generation circuit 15 receives the contents and locators of the row 9 column counters RC and CC from the character display L1i 112.

When the start addresses R8 and CB from the start register 13 match, the switching signal GP is turned on at the timing of the tie. In FIG. 2, the GP is turned on in the g-row and n-th column. Signal G
When P turns on, the start address ΔXs of register 14
, .DELTA.Y- are loaded into the address register 10.9, respectively, and reading from the data area 8 of the memory 8 is started. Since the contents of the address register 10.9 are updated every time data t is read, when the end address ΔXml of the read register 14 matches Yl, the read t ends.

Incidentally, the signal GP is turned off when the contents of the counters RC and CC match the end address R ecl of the processing register 13. This does not necessarily coincide with the end of reading from data area 8a. The reason for this is that the window area 7m in the jIE3 diagram may be set as wide as the data area 8m. In this manner, the gate 12 is opened while the signal GP is on, and the graphic data in the data area 8m is displayed in the window area 7m.

Claims (1)

[Claims] Specify an arbitrary data area on the bit pattern memory that stores graphic data, and specify an arbitrary window area on the screen to display the character pattern generated from the middle Yatsukume generator. 7. A display device according to claim 7, wherein the graphic data read out from the data area is displayed in the window area.