JPS63136078A - Bit map display controller - 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 Field of the Invention The present invention relates to a display control system, and more particularly to attribute functions for characters, images, etc. in color display control using a % bitmap system.

2. Description of the Related Art Conventionally, in this kind of bitmap type display side@l device, in order to link characters, images, etc.
This was realized using the circuit configuration shown in the figure. The prior art will be explained below using FIG. 3. The blinking function is a type of attribute function related to screen display, and is a function that causes characters or images on a part of the screen to blink.

The bitmap display control device controls the display of characters and images on the screen using software from the microprocessor via the processor bus 20/. 'Also,
Regarding the transfer of the character f image, the window is transferred between the window memory U and the video memo IJu using a mover.

In order to realize the blinking display function, this transfer function is used to transfer the positive logic display area (blinking target area) on the original video memory to the negative logic [reverse] prepared on the window memory. ) is transferred from the window memory 3 to the video memory, and the positive logic pattern is replaced with the negative logic pattern.

Blinking is achieved by exchanging this positive/negative pattern at regular intervals.

This fixed time timer is processed by the microprocessor 10 software.

Furthermore, in the case of a color display control device, the contents of a multi-layer video memory can be stored in a foreground pattern such as a single character section (
It is necessary to replace the background pattern (table logic pattern) with the background pattern (actual logic pattern), and therefore, if it is color, it is necessary to transfer multiple layers.

Problems to be Solved by the Invention In the above-mentioned conventional bitmap display control device, in order to realize the blinking function, it is necessary to frequently transfer the front/back logic patterns on the Image Pasco 02 at regular intervals. be.

However, monitoring this fixed-time timer using software can reduce the load on the microprocessor.
This poses a major problem in that it increases the amount considerably. Due to this increased load on the microprocessor, from the perspective of the entire system, the load on display-related functions increases, and other I/O
There is a drawback that it affects the control of 10 devices and the like.

The present invention has been made in view of the above-mentioned conventional situation,
SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a new pit map display control device which makes it possible to eliminate the above-mentioned drawbacks inherent in the conventional technology.

Means for Solving the Problems In order to achieve the above objects, a pit map display control device according to the present invention includes: (1) a microprocessor for controlling the entire display control, a window memory, a mover and a video memory for performing raster operations, and a blind. a blinking memory, a blinking timer circuit, a switching circuit that switches between the output of the video memory and the blinking memory based on the output of the blinking timer circuit, and a display connected to the output of the switching circuit. It is composed of:

Embodiment Next, a preferred embodiment of the present invention will be specifically explained with reference to the drawings.

! / is a block diagram showing an embodiment of the present invention.

Referring to FIG. 1, the parts of the bitmap that perform normal functions will first be described. The image bus 102 is controlled via the processor interface circuit F@tO from the microprocessor bus 10/ which controls the entire display control. Transfer of single character patterns and image patterns is performed by the mover/! Raster operations are performed via the image bus 102 by the window memory /lI. The multilayer video memo IJ t3 actually has a one-to-one correspondence with the screen of the display g37t, and the screen size etc. are displayed on the screen according to four rules by the screen display control circuit //.

The blinking function according to the second aspect of the present invention is achieved by adding a further blinking memory/co, a blinking timer 16, and a switching circuit/7 to the circuit described above.

Blinking can be performed using the following two steps.

First of all, the blinking period is set in the blinking timer/6 by software using the microprocessor (
This setting only needs to be done once). As a result, the output of blinking timer/6 is turned on/off at the blinking period.
The OFF signal 103 serves as a switching control input for the switching circuit/7.

Second, write "All /" in the area on the blinking memory 7.2 that requires blinking (the initial value is o", and the part where l" is written corresponds to the blinking area). ).

Blinking display is performed by setting only these two procedures from the microprocessor. That is,
Original video memo 17/, 7 output signal 104! and the output signal 10.3 of the blinking memory/co are the switching circuit/? A final signal 107 is created by adding blinking to the output of the video memory /3 according to the period of the blinking switching signal 10S, and is sent to the display section /g, where the pattern of the video memory 13 is displayed. At the same time, only the blinking target area is displayed blinking.

Next, the switching circuit/7 in this embodiment shown in FIG.
In order to understand the details, explanation will be given using Figure 1. FIG. 1 is a block diagram showing details of the switching circuit 17 shown in FIG. The two signals, the multilayer video output signal 101I (table logic) and the signal 10Ir which has become real logic through the background conversion circuit, are sent to the multiplexer/?
The first pattern or the second pattern is selected by the multiplex control signal 109 and becomes the final pattern of the output signal. Multiplex control signal 1
0′? is the AN between the blinking memory output signal 103 and the output signal of the blinking timer/B.
It is created by AND K using D circuit. In other words, normally the video signal 10 is the final video signal #i, but the signal 10 is used only in the blinking area #i and only during the inverted display period of the blinking timer/6.
3 and the signal lO5 are ANDed, the multiplex control signal 109 is output, and the real logic pattern 10t is output as the final pattern 107.

As described in detail, according to the present invention, a blinking memory, a blinking timer circuit, and a switching circuit for switching between a video memory output and a blinking memory output are added to the conventional bitmap display control circuit. This provides the effect that the blinking display function can be executed with almost no load on the microprocessor.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 1 is a block diagram showing details of a switching circuit according to the present invention, and FIG. 3 is a diagram of a conventional circuit. 10... Microprocessor interface circuit, /
/...Screen display control circuit, /2...Blinking memory, 13...Video memory, /lI...Window memory, 15...Mover%/6...Blinking timer circuit , /7...Switching circuit %lza...Display section, 19...Two-person selection circuit (multiplexer),
J...Microprocessor interface circuit, 2/
... Screen display control circuit %22 ... Video memory, 2
3...Window memory, coq...mover. 7..AND circuit, 101..microprocessor bus, 102..image bus, 103..blinking memory output signal, 104t...video memory output signal, 10! ...Blinking timer output signal, 101. ...Synchronization signal for screen display, 107.
...Final data signal for screen display, 10g...Real logic video memory output signal, 109...Control signal for two-person selection circuit, 0/...Microprocessor bus, 202
...Image bus, 20J...Video memory output signal, Koi...Synchronization signal for screen display Patent applicant: NEC Corporation Representative Patent attorney: Yutabe Kumagai ζ 1 Figure 2

Claims (1)

[Claims] A bitmap color display control device includes a microprocessor that controls overall display control, a transfer control circuit that performs raster operations, a window memory, a multilayer video memory, a blinking memory, and a blinking timer circuit; A bitmap display comprising: a switching circuit that switches between the output of the blinking memory and the output of the video memory based on the output of the blinking timer circuit; and a display unit connected to the output of the switching circuit. Control device.