Receiver teletext

Abstract

Abstract PURPOSE:To initialize a display memory without writing initial value data on the display memory by a microcomputer, by providing a means which initializes the memory. CONSTITUTION:Chip-enable signals CE1 and CE2 are generated by frequency division outputs XA0 and XA2 of a display clock, and an output-enable signal OE is generated also, and a write-enable signal WE is in level 1 as it is. When an output REC of an initialization control register 8 is '1', the initializing operation is performed, and the signal WE is outputted in the display period, and the signal OE is '1' as it is. Addresses re given to display memories 4 and 5 by an address A' from a display address generating circuit 2, and a data switching circuit 6 switches and connects the output of an initial value data register group 7 to data busses VD0 and VD1 by frequency division outputs XA1 and XA2 to initialize all display areas of memories 4 and 5.

Inventors

• 👤 Hiroyasu Shinpo
• 👤 新保　博康
• 👤 Yuichi Shiotani
• 👤 塩谷　友一
• 👤 Kazumi Kawashima
• 👤 河島　和美

Bibliographic Details