DP8350 Datasheet | National Semiconductor

Description The DP8350 Series of CRT Controllers are single- chip bipolar (12L technology) circuits in a 40'pin package. They are designed to be dedicated CRT display refresh circuits. The CRTC also provides system sync and program inputs including 50/60 Hz control, system clear, external character/1 ine rate clock, and character generator pro- gram. The CRT Controller (CRTC) provides an internal dot rate crystal controlled oscillator for ease of system design. For systems where a dot rate clock is al ready provided, an external clock input may be used by the CRTC. In either case system synchronization is made possible with the use of the buffered Dot Rate Clock Output. The DP8350 Series has 11 character generation related timing outputs. These outputs are patible for systems with or without Iine buffers, using character ROMS, or DM8678- type latch/ROM/shift register circuits. 12 bits (4k) of bidirectional TRI- STATE@ character memory addresses are provided by the CRTC for direct interface to character memory. The DP8350 Series operates on a single +5 V power supply. Outputs and inputs are TTL patible. Features - Internal crystal controlled dot rate oscillator - External dot rate clock input - Buffered dot rate clock output - Timing pulses for character generation - Character memory address outputs (12 bits) - Internal cursor address register - Internal row starting address register - Top- of- page address register (for scrolling) Three on- chip registers provide for external loading of the row starting address, cursor address, and top- of- page address. A plete set of video outputs is available including cursor enable, programmable vertical blanking, program- mabie horizontal sync, and programmable vertical sync. The DP8350 Series CRTC provides for a wide range of programmability using internal mask p.rogrammable ROMs: - Programmable horizontal and vertical sync outputs - Programmable cursor enable output - Programmable vertical blanking output - 50/60 Hz refresh...