No Cache turns 68040 processor caches in the Quadras off and on. This allows those applications that do self-modifying code no-nos to operate. No Cache doesn't change the operating mode of the caches: it simply disables them. When you switch the caches back on, they resume in the previous mode (typically copy-back). No Cache works by issuing Supervisor Mode 68040 instructions to alter the contents of the cache control register. This has two implications. First, since the organization of the 68040's cache control register is different from the 68030's, No Cache won't work with 68030-based Macs. Second, No Cache won't work when a Mac is running virtual memory, since the Mac OS runs in User Mode so that the page-fault mechanism can operate. While No Cache won't crash a Quadra running virtual memory, the caches aren't disabled either. I hate to think where that intercepted exception is going, so I don't recommend using No Cache at all with virtual memory.
How to:
Simply launch No Cache. A dialog box with two radio buttons appears. One of these buttons is active to indicate the 68040's current cache settings (either off or on). To change the cache operation, click on the appropriate radio button (say, off). No Cache does its thing, then quits. To turn the caches back on, simply re-launch No Cache and click the On button. Make sure you quit the offending application before changing the cache states. No rebooting is necessary, as is the case with Apple's Cache Switch Control Panel. To its credit, Cache Switch does work with virtual memory. I needed the ability to run both errant and compatible Mac applications on the fly, more than I needed virtual memory, and so No Cache was born.
Disclaimer:
This software is provided "as is" without any warranty of any kind, and the author and distributor expressly disclaim all implied warranties, including but not limited to the implied warranties of merchantability and fitness for a particular purpose. The entire risk as the results and performance of this software and written materials is assumed by you.
Cost:
In the spirit of No Cache's name, Overpriced Software requests no cash. However, if No Cache has saved you some grief, and you'd like to see more life-saving hacks, feel free to send some money to subsidize our Jolt/Twinkie habits to:
Overpriced Software
P.O. Box 202
Peterborough, NH 03458
Also, check out another nifty Overpriced Software product, DepthKey, which allows you to change your Mac's screen depth. It's easier to use than an alias of the Monitors cdev on the Desktop.
Contact me at the following addresses, with suggestions or bug reports:
