On 08/14/2010 08:56 PM, Daniel Ferguson wrote:

You'll notice that,
SPI pin, MOSI(P0.18), is seemingly unexposed to the outside world.
So from my fresh-faced perspective, SPI is unusable on this board as-is.

If I'm reading the lines right, P0.18 goes over to BUT2. So it's not as easy as it could be, but you could probably tap it with a piece of wire-wrap wire.

In case I truly cannot use SPI(sans SSP), I need a backup plan...
SSP0 goes to the LCD. And, it's not exposed via headers as-is. so SSP0 is
out.

That leaves me with SSP1
So, SSP1 will do, but it doesn't let me use the interrupts that the SPI/SSP0
give me.

I found the LPC23xx manual...looks like there's a SPI port and two SSP ports, which can operate in SPI mode. So...how are they pinned out? ... Looks like SSP1 is pinned out to P0.[789], on EXT-2. SSP0 shares pins with SPI. SSP0 can also get pinned out to P1.23...which goes over to the LCD. I haven't chased it all out, but I wouldn't be surprised if you can hook up SSP0 to the LCD by selecting some pins, and connect it somewhere else by selecting other pins.

I haven't read thru the SSP chapter, but it's not entirely unusual for one of two otherwise-identical peripherals to have a little extra love in the interrupt or control-line department.

If you absolutely need interrupts to write your code, you might be screwed, but IME on the LPCs, you can abstract stuff away pretty well, and just fake the interrupts by busy-waiting or whatever. You can get your code running, and when you get the real hardware built, you shouldn't have _that_ much extra work to do.

What are you putting on the SPI bus?
--
Mersenne Law LLC  ·  www.mersenne.com  ·  +1-503-679-1671
- Small Business, Startup and Intellectual Property Law -
1500 SW First Ave. · Suite 1170 · Portland, Oregon  97201

_______________________________________________
psas-avionics mailing list
psas-avionics@lists.psas.pdx.edu
http://lists.psas.pdx.edu/mailman/listinfo/psas-avionics

Reply via email to