
 DMP481 is a utility that can be used to patch the screen resolution parameter
 table in 82C481 drivers. Each supported screen resolution has a section in the
 .DRV file which provides values for the various 481 registers and the 404
 clock chip. Each section is 'marked' with a unique 16 byte header string which
 is of the form "VRESxxxxxxxxxxx@".
 
 The Driver Modification Program is invoked by typing  DMP481<cr> on the DOS
 command line. DMP will then display 
  
 ~
 
 which is the DMP command prompt.
 
 Following is a list of DMP481 Commands.
 
 COMMAND		ACTION 
---------	       --------	

   O <file>       (O)pen <file>.DRV for editing. 
   
   S <string>     (S)earch <file>.DRV for VRES<string> parameter section. This
   		  searches the .DRV file until it finds the parameter section
		  for the selected resolution. An error message is displayed if
		  the selected resolution string is not found.
		  This command MUST be executed before any D(isplay) or E(dit)
		  commands are done, since these are all based on the parameter
		  values in the resolution tables. Following is the list of
		  resolution parameter sections supplied in CHIPS 82C481 drivers.
		  
		  <string>   resolution
		  --------  ------------
                    480       640x480
                    480_70    640x480 70Hz
                    600       800x600
                    600_72    800x600 72Hz
                    768       1024x768
                    768_70    1024x768 70Hz
                    768I      1024x768 Interlaced
                    1024      1280x1024
                    1024I     1280x1024 Interlaced
                    1024_76   1280x1024 76Hz
		    
		  For example, the following command would select for editing
		  the parameter section for screen resolution 800x600.
		   
		  S 600<cr>
		  
   E <reg> <data> (E)dit the contents of <reg> parameter for selected screen
		  resolution. See below for list of register mneumonics.
		  For example, the following command will modify the H_TOTAL
		  parameter:
	
		  E H_TOTAL 1234<cr>
		  
		  <data> numbers are assumed to be HEX.
   
   D <reg>        (D)isplay the contents of <reg> parameter for selected 
   		  screen resolution.
		  
   
   		  	<reg> Register Mneumonics
 		      -----------------------------
		 
                  h_total, h_disp, h_sync_strt, h_sync_wid
		  v_total, v_disp, v_sync_strt, v_sync_wid
		  h_ab_strt, h_ab_end, v_ab_strt, v_ab_end
		  vclk, mclk
		  * (display all, NOT valid for edit)
		  
		  <reg> mneumonics can be either upper or lower case.


   C <file>       Write and Close modified <file>.DRV. The driver file with the 
		  modified parameters is written back to disk as <file>.DRV. A
		  copy of the original driver has been saved as <file>.DSV.
		  Only one screen resolution parameter table can be modified at
		  a time. If you wish to modify multiple resolutions, the file
		  must be (o)pened and (c)losed multiple times.
		  
   Q              Exit DMP481. Write and Close modified <file>.DRV

   % <dos cmd>    MSDOS command/escape
