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 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 (O)pen .DRV for editing. S (S)earch .DRV for VRES 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. 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 E (E)dit the contents of 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 numbers are assumed to be HEX. D (D)isplay the contents of parameter for selected screen resolution. 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) mneumonics can be either upper or lower case. C Write and Close modified .DRV. The driver file with the modified parameters is written back to disk as .DRV. A copy of the original driver has been saved as .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 .DRV % MSDOS command/escape