View source for R32V2020 ANSI Terminal with UART Interface

== Description ==

The ANSI terminal is an FPGA implementation of an ANSI display. The original design was created for [http://searle.hostei.com/grant/Multicomp/ Grant Searle's Multicomp project]. 

The terminal implements a subset of [http://ascii-table.com/ansi-escape-sequences-vt-100.php ANSI Escape codes].

The display has hardware cursor support and displays 80 characters per row times 25 rows of characters.

The R32V2020 implementation removes the [[PS-2-Keyboard|PS/2 keyboard]] which had UK-101 key mappings.

== Interface ==

The interface to the ANSI terminal is a [http://www.swtpc.com/mholley/Notebook/Hardware_ACIA.pdf 6850 ACIA] (UART) interface. This interface consists of two memory mapped 8-bit ports - one status/control port and the data port. 

== Performance ==

* Measured the performance of the ANSI terminal using the R32V2020 CPU
** Char Write Speed = 0.78 uS/char or 1.2M chars/sec
** Screen Clear Speed = 100.2 uS
** Screen Scroll Speed = 3.94 uS
* Performance is much faster than the 60 Hz frame refresh rate
* Might make sense to add polling for Vertical Sync or possibly double-buffering