Microprocessor Control of Loading Character Data to Gas Panel
Original Publication Date: 1986-Jul-01
Included in the Prior Art Database: 2005-Mar-09
An alphanumeric gas panel display terminal includes a microprocessor 10 to perform datastream and keystroke functions, and a second microprocessor 12 to perform all the functions that would be provided by a conventional hardware gas panel adapter. The second microprocessor 12 must control directly the loading of serial data to a gas panel 14 to keep the data transfer loop as short as possible in order to avoid reducing the data transfer rate. On receiving a command to write a row of characters on the gas panel, the microprocessor 12 fetches the characters and attributes from the main character buffer RAM (random-access memory) 16 in which they are stored and loads them into the row buffer area 18 of its own high speed working storage RAM.