Hi
I got the max3140 working (at least in transmit - working on receive) using the 1000000Hz SPI rate. My problem? Simple stupidity! I put a printf statement right after I asset chip select and that blew my framing. I'll probably post it to the blog if it's interesting enough.
Nice work! Yeah, printf takes a long time if the baud rate is low (remember 9600 modems?!), so shouldn't really be used in timing critical sections at those speeds. Like most bugs, it is obvious now you've seen it, but until then...
Yeah, if you get it working, it'd be great if you could put up a max3140 example in the cookbook. Feel free to add photos of your handiwork too :) Chris got hold of some of those chips, so we then may be able to reproduce it.
Great stuff!
Simon
Hi,
You said you are working on an RS485 interface (as I am) Are you planning to use the MAX3140? I am having trouble determining the SPI frequency. I am using spi.format(16,1,1) but the returns don't really make any sense. If you are using this part could you tell me what you are using for these parameters?
Gary