The SPI of the PICs is in my view superior of the one implemented in LPC. In LPC the maximum clock is lower (per Main clock) and you have no double buffering. From the User Manual: /12.2.8 Write Collision As stated previously, there is no write buffer between the SPI block bus interface, and the internal shift register. As a result, data must not be written to the SPI data register when a SPI data transfer is currently in progress. The time frame where data cannot be written to the SPI data register is from when the transfer starts, until after the status register has been read when the SPIF status is active. If the SPI data register is written in this time frame, the write data will be lost, and the write collision (WCOL) bit in the status register will be activated. / But I think that Philips knows that, because in the newer devices, one of the SPI is a SSP. And now you have not one 1 char in the buffer, but 8. and the maximum clock rate is higher too (from 7.5Mhz to 30Mhz). Mauricio Gus wrote: > Hello, > > On SPI, is the shift register different than the data register? In > other words, if I am a slave, can I put data in the SPI data register > any time even while a transition is in progress? On PIC micros this is > safe practice but what about LPC? > > Thanks, > > Gus > > > > > > SPONSORED LINKS > Microcontrollers > <http://groups.yahoo.com/gads?t=ms&k=Microcontrollers&w1=Microcontrollers&w2=Microprocessor&w3=Intel+microprocessors&w4=Pic+microcontrollers&c=4&s=95&.sig=mfaAujKZXA2Z_vxre9sGnQ> > Microprocessor > <http://groups.yahoo.com/gads?t=ms&k=Microprocessor&w1=Microcontrollers&w2=Microprocessor&w3=Intel+microprocessors&w4=Pic+microcontrollers&c=4&s=95&.sig=9jjd2D3GOLIESVQssLmLsA> > Intel microprocessors > <http://groups.yahoo.com/gads?t=ms&k=Intel+microprocessors&w1=Microcontrollers&w2=Microprocessor&w3=Intel+microprocessors&w4=Pic+microcontrollers&c=4&s=95&.sig=OMnZuqMZX95mgutt4B-tDw> > > Pic microcontrollers > <http://groups.yahoo.com/gads?t=ms&k=Pic+microcontrollers&w1=Microcontrollers&w2=Microprocessor&w3=Intel+microprocessors&w4=Pic+microcontrollers&c=4&s=95&.sig=Malspbd0T4Rq3M4Q0nHrfw> > > > > ------------------------------------------------------------------------ > YAHOO! GROUPS LINKS > > * Visit your group "lpc2000 > <http://groups.yahoo.com/group/lpc2000>" on the web. > > * To unsubscribe from this group, send an email to: > lpc2000-unsubscribe@yahoogroups.com > <mailto:lpc2000-unsubscribe@yahoogroups.com?subject=Unsubscribe> > > * Your use of Yahoo! Groups is subject to the Yahoo! Terms of > Service <http://docs.yahoo.com/info/terms/>. > > > ------------------------------------------------------------------------ > [Non-text portions of this message have been removed]
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Re: [lpc2000] SPI and SSP double buffered?
2006-01-27 by Mauricio Scaff
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