This final release of the Windows 95 device driver can control the Philips CM-205MS, and CM-206 CDROM drives. To install the driver, use the following procedure: 1) Make backup copies of all the following files: CONFIG.SYS, AUTOEXEC.BAT files. SYSTEM.DAT and USER.DAT. ***NOTE*** SYSTEM.DAT and USER.DAT are hidden, system, read-only files and are located in the C:\WINDOWS directory. These two files comprise the REGISTRY for your system. If they get damaged or corrupted in any way, your system will not start and you'll probably have to re-install Windows95. Exercise EXTREME caution when working with these files. For more information on the REGISTRY, see the Win95 help utility. 2) Remove the DOS driver line (DD250MS.SYS or DD260.SYS) from your active CONFIG.SYS file and remove the MSCDEX line from your active AUTOEXEC.BAT file. 3) From the Windows 95 Control Panel: * Select the 'Add New Hardware' option. * You DO NOT want Windows to auto detect the hardware. * Add a new CDROM controller. * With the setup diskette in drive A, select the HAVE DISK option. * Complete the installation by following the on screen instructions. 4) You must re-boot the system after installing the driver. _______________________________________________________________________________ Setting Interrupt Jumpers: The driver will utilize a 'Polling' method unless directed to use Interrupts by the Registry Entry for the device. Polling is fine for casual usage. However, to properly run applications which are CDROM intensive, interrupts should be used. Use the following procedure to enable interrupts for the CDROM device(s): 1) Set the interrupt jumper on the CM-260 host adapter card to the desired level. The IRQ you select should not conflict with any other device in your system. If you are upgrading from Windows 3.1(1) you will not not need to change this setting unless you have added new hardware. 2) From a Windows 95 MS-DOS prompt, run the Registry Editor (REGEDIT) and modify the Registry Entry under the Philips CDROM device as follows: HKEY_LOCAL_MACHINE\SYSTEM\CURRENT_CONTROL_SET\SERVICES\CLASS\ADAPTER \0000\AdapterSettings 3) Edit the AdapterSettings String using the following syntax: IRQx=y where x is the device number 0, 1, or 2 and y is the IRQ setting on the adapter card. If you are installing only one Philips CDROM drive, use device number 0. The Registry tree entry will look something like this for a single host adapter set to IRQ 15: HKEY_LOCAL_MACHINE\SYSTEM\CURRENT_CONTROL_SET\SERVICES\CLASS\ADAPTER \0000\AdapterSettings:IRQ0=15 4) Windows 95 has a performance option that can be set from the Control Panel 'System' icon. This option allows you to optimize CDROM access for a dual speed (2X) drive such as the CM206. 5) The system will need to be rebooted for the changes to take effect. Known Issues; 1). Autoplay is not supported for audio CD's. 2). The CM-205MS and CM-206 CDROM drives were designed to be used in the MS-DOS and Windows 3.x environments. Several unique features were incorporated into the design of these drives to enhance performance. While these design features have proven very effective in real mode environments, they are not entirely compatible with protected mode operating systems like Windows 95. Regardless of the operating system, CDROM transfer rate is heavily dependant of data buffering. In real mode (DOS, Windows 3.x) buffering was the responsibility of the device driver and our prodcuts were designed to take advantage of this. In the Windows 95 environment, the operating system has complete control over system resources and allocates a percentage of them to peripherals as it sees fit. This method of peripheral control is in direct conflict with the design of the CM-206 drive. If the percentage allocated to the CDROM drive is too low, the result is poor transfer rate performance. The following parameters can affect the ammount of available system resources; 1). Processor speed. 2). System RAM. 3). Cache size (both processor and peripheral). 4). Running multiple applications simultaneously. 5). Running hardware intensive applications (.AVI or .MPG files, etc.). Our tests show that, in order to achieve marginally acceptable CDROM performance, a 486 DX-80 processor is the minimum required. Additionally, applications using full motion video require a minimum of 8 megs of RAM and a 32-bit video card and the ammount of RAM required will increase drastically if other applications are run simulateously. If the transfer rate of your CM-205MS or CM-206 CDROM drive is unacceptably slow, try increasing the ammount of available system resources as described above, or use the DOS drivers in real mode. The real mode drivers are not subject to control by the Windows 95 operating system and are able to run much more efficiently.