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Info for 990189v


====== TM 990/189 University Board microcomputer with University Basic and Video Board Interface (1980) ======




===== Usage =====

This driver emulates a TM990/189 with University Basic and the optional Color Video Board.

You can use all the video opcodes documented in the University Basic Manual.

The optional demonstration EPROM set includes demonstration programs. They can be loaded with LOAD 0, LOAD 1, LOAD 2 and LOAD 3. Some programs are supposed to do some user interaction, but they were set up to run in demo mode, so that you must edit the source code to run the programs interactively: for instance, to play the brick-wall game, you must type 'LOAD 2', then enter '5 SP=0' to disable demonstration mode, then 'RUN'.

There are two undocumented built-in Basic instructions that can be used if you have the demonstration EPROMs installed: PLOT and JOY. These instructions are not fully implemented in University Basic, and they rely on assembly language subroutines located on the Demonstration EPROMs.

The PLOT instruction draws lines in multicolor mode (which is entered by "MODE 8" through "MODE 15"). "PLOT 0,n" sets up the screen for multicolor mode, and must be executed before any other PLOT instruction (n is ignored). "PLOT 1,c[,x,y]" sets the pen color to c, and sets the coordinates of the lower left corner to (x,y). "PLOT 5,x,y" sets the pen position absolutely, and "PLOT 3,x,y" sets the pen position relatively to the current pen position. "PLOT 6,x,y" draws a line from the current pen position to a new pen position
expressed absolutely, and "PLOT 4,x,y" draws a line from the current pen position to a new pen position expressed relatively to the current pen position. "PLOT 2,x,y" and "PLOT 7,x,y" do not do anything.

The JOY function reads the state of either joystick. "JOY 0" reads the analog X-axis for joystick 1, "JOY 1" reads the analog Y-axis for joystick 1, "JOY 2" reads the button state for joystick 1, "JOY 3" reads the analog X-axis for joystick 2, "JOY 4" reads the analog Y-axis for joystick 2, and "JOY 5" reads the button state for joystick 2.



===== History and Trivia =====

The Color Video Board was released in 1980. It includes a TMS9918 VDP, a joystick interface, and two EPROM sockets. The VDP enables to display colorful graphics on a video monitor.

This board was not designed by TI, but an external society (Eyring Research Institute).

//(info from Raphael Nabet, author of the MESS driver)//




Generated on Sun Jul 19 10:17:28 2009