| ??? 02/15/06 09:36 Read: times |
#110019 - precise??? Responding to: ???'s previous message |
Richard Erlacher said:
Nevertheless, since it's possible to get all the popular baud rates above and including 4800 from a 12 MHz crystal, and derive other benefits associated with precise timing from that as a timebase The timing is always as precise as the crystal is, usually tens of ppm; regardless of the actual value of the crystal. If you have attached a device which requires a particular clock and providing a clock from '51, that's an another issue. For example, if a MIDI bus is attached, it's timing requirement almost prohibitively requires using 12MHz/24MHz crystal on the 12-clocker (http://www.8052.com/forum/read.phtml?id=109864 and response). There are similar examples, although quite rare. Obviously, you are working with something alike - it would help in the discussion if you would be more specific. However, in most cases, the "convenience" IS irrelevant - see the recent thread on counter using the 11.0592MHz crystal - it IS precise and also quite simple to accomplish, just it requires some basic math and a bit of thinking. I would not call these as inconvenience... Jan Waclawek |
