Free Electronic Circuits & 8085 projects

Electronic projects with circuit diagram and 8085 microprocessor projects.

Image processor 6538 and 8031 Interface circuit

Published on Oct 27 2010 // Micrcontroller circuits

Image processor6538 and 8031 Interface circuit

6538 is a Nintendo dedicated video image processor chip, which has a very strong image processing capabilities. If the 6538 to 8031, putting it a strong image processing for industrial control area, will even more powerful microcontroller. And 6538 is very common in the market, the price is only ten dollars a piece, in the field of industrial control applications is very promising.

Common market, Taiwan’s United Microelectronics Corporation’s 6538 production of UMC6538, the pin arrangement shown in Figure 1. It can support fewer peripheral circuits of image processing, direct output composite video signal can be directly sent to the monitor display. If through RF modulation, can be wired or wireless means in color or black and white images on a TV show.

6538 can display a resolution of 256 × 240 points in the color image, each point has 52 colors to choose. 6538 shows the image formed by the superposition of four pages, front to back and so is the cartoon 0, background page, the cartoon one, the end of the background page. The page can be displayed by the software switch or not. 4 superimposed on this page, the page images can be in front of the back cover page image, so that the screen has a strong three-dimensional. 4 pages in the background of the page only holds the display buffer, the background page for a total of 4, the buffer in 6116, the actual can only use two. Cartoon page to display 64 blocks of 8 × 8 dot matrix graphics, buffer unit in 6538, modify the parameters of cartoon image on the screen make a point to any mobile units, at the end can only display a single color background page can not display graphics, do not total buffer unit, the color selected by the software. 6538 and 8031 of the interface shown in Figure 2. 6538 to 6502 bus structure 8031 can not be directly connected at the same time, through the external interface to the connected, it will take a lot of external interfaces, the operation is convenient. Figure 2 After the 8031 change to read and write signals so that 6538 can be directly linked to the system bus in 8031, can save a lot of external interfaces, but also easy to operate, you can directly access the 6538 MOVX instruction. Figure 2 6538 the R / W signal to the 8031 A8 on an address line, which requires the 8031 restrictions on access to 6538 address, when asked to write 6538 A8 is low, read 6538 when the A8 is high.

6538 and 8031 through the communication register 8, 8031 by accessing these registers control the display and access to the display buffer and the font. A character from the 2764 constitution, which can cure 512 block of 8 × 8 dot matrix graphics, these graphics block can be ASCII characters or cartoon graphics, it can be the equivalent of four Chinese characters dot matrix graphics 8 × 8 block. In 2764 the suggested cure 128 ASCII characters and 96 commonly used Chinese characters dot-matrix, which can meet most of the occasions, if you want to display any Chinese characters can be replaced by 6264 to 2764, the high-capacity system of Chinese characters library hanging in 8031, when To display a character, the 8031 dot-matrix through the interface to the character of the character sent to 6538 6264, so 6538 can display any Chinese characters.

In order to process images in real time, 6538 also provides an interrupt output INT, the signal switch control by software, when allowed to interrupt, INT-ended flyback period in a given image width is 1.286ms, low pulse frequency of 50Hz signals, can interrupt the signal to synchronize an image of each and do not take up too much machine, a program designed to bring great convenience.

For example, to the screen "COMPUTER image processing" a few words, font to 2764, which solidified with ASCII characters and the "image processing" and other Chinese lattice.