Lpc2000

At 10:38 21.12.2005, you wrote:
>--- In lpc2000@yahoogroups.com, Herbert Demmel <dh2@d...> wrote:
> >
> > Hi,
> >
> > thank you for your valuable input, but (as already mentioned in an
>earlier
> > email) I forgot to tell, that I need an external data bus as well.
> >
> > To summarize the requirements:
> >
> > ARM7 with JTAG
> > Flash >= 128k (better 256k)
> > RAM >= 32k
> > USB (should be 2.0)
> > 2 x serial ports, 2 x SPI, 2 x I2C, 1 x ADC (>= 10 bit), PWM
> >
>What do you need the external data bus for?  I (and many others)
>have simulated an external data bus by just bit-banging the GPIO
>ports.  You don't get the same performance, but you can still get it
>quite fast for most intents and purposes.  This is particularly
>useful on the LPC213x or LPC214x because of the inexpensive
>processor.  I, for example, have an external 2MB sram chip hooked up
>to GPIO ports.  You can also use serial flash, for example the
>M25P40.

I agree, BUT: Try to hook a display controller like Epson's S1D13A05 - see 
at 
http://www.eea.epson.com/go/Prod_Admin/Categories/EEA/IC/ASSP/Display_IC/LCD_Controllers/displayItem?itemId=S1D13A05&categoryId=EEA.IC.ASSP.Display_IC.LCD_Controllers 
- to a 64 pin LPC214x and keep free enough pins for some other I/O :-(

Besides that, in this case bus speed becomes an issue when you imagine that 
you want to write 320x240 color pixels with 16 bit per pixel, especially 
when you go up to 640x40 pixels ...

Regards
Herbert





>SPONSORED LINKS
><http://groups.yahoo.com/gads?t=ms&k=Microprocessor&w1=Microprocessor&w2=Microcontrollers&w3=Pic+microcontrollers&w4=8051+microprocessor&c=4&s=93&.sig=tsVC-J9hJ5qyXg0WPR0l6g>Microprocessor 
><http://groups.yahoo.com/gads?t=ms&k=Microcontrollers&w1=Microprocessor&w2=Microcontrollers&w3=Pic+microcontrollers&w4=8051+microprocessor&c=4&s=93&.sig=DvJVNqC_pqRTm8Xq01nxwg>Microcontrollers 
><http://groups.yahoo.com/gads?t=ms&k=Pic+microcontrollers&w1=Microprocessor&w2=Microcontrollers&w3=Pic+microcontrollers&w4=8051+microprocessor&c=4&s=93&.sig=TpkoX4KofDJ7c6LyBvUqVQ>Pic 
>microcontrollers
><http://groups.yahoo.com/gads?t=ms&k=8051+microprocessor&w1=Microprocessor&w2=Microcontrollers&w3=Pic+microcontrollers&w4=8051+microprocessor&c=4&s=93&.sig=1Ipf1Fjfbd_HVIlekkDP-A>8051 
>microprocessor
>
>
>----------
>YAHOO! GROUPS LINKS
>
>    *  Visit your group "<http://groups.yahoo.com/group/lpc2000>lpc2000" 
> on the web.
>    *
>    *  To unsubscribe from this group, send an email to:
>    * 
> <mailto:lpc2000-unsubscribe@yahoogroups.com?subject=Unsubscribe>lpc2000-unsubscribe@yahoogroups.com 
>
>    *
>    *  Your use of Yahoo! Groups is subject to the 
> <http://docs.yahoo.com/info/terms/>Yahoo! Terms of Service.
>
>
>----------


[Non-text portions of this message have been removed]