| ??? 12/17/06 08:27 Read: times |
#129626 - Using a crystal Responding to: ???'s previous message |
to be honest, I'm a bit upset that I had to trim the uController at all. they are are spec'd at +/- 1% accuracy, so I assumed that the 1% drift would be fine for the serial port as, the serial ports themselves are supposed to be pretty tolerant, I can't remember the exact specs, but +/- 2% of the specified bit rate on the serial port seems to ring a bell.
For interest the uC was running at 7.16 MHz not the 7.373MHz I'll have to read the datasheet again to see if the 1% drift was after they had been trimmed. Anyway I have had my PCB's manufactured without the provision of a crystal, so now I am stuck with the internal RC. It actually was quite appealing not having the crystal as I was able to use all the pins for IO (apart from gnd and supply) Next board revision, I'll be fitting a crystal! Regards Marshall |
| Topic | Author | Date |
| LPC9xx Serial Issue - MSBit always set | 01/01/70 00:00 | |
| Using a crystal | 01/01/70 00:00 | |
| Crystal | 01/01/70 00:00 | |
| the Acqura (can) clock itself | 01/01/70 00:00 | |
| Using internal Clock | 01/01/70 00:00 | |
| use CLKOUT and a scope | 01/01/70 00:00 | |
| Yep - I'll give it a go thanks | 01/01/70 00:00 | |
| It Works - Thanks for all the help | 01/01/70 00:00 | |
| Best to chip the chip specs | 01/01/70 00:00 | |
| Using a crystal | 01/01/70 00:00 | |
LPC925 Internal RC Osc | 01/01/70 00:00 |