Is there a “best” way to connect the nRF2401 IC to an Atmel AVR? Can the SPI be used in anyway to help the throughput? Instead of the slower bit banging?
Any ideas?
Rick.
Unfortunately since the data xmit/recv is on the same pin, spi won’t help (you could probably do some tricks to get it to work with some external components, but it would take a little engineering)…
I put together code to interface with an AVR; it’s over at avrfreaks.net in the academy section.
Spi is no problem and you can go to the nordic website there is app note on connecting to spi.
There is an appnote from NVLSI - “Interfacing nRF2401 with SPI” - showing how to use two resistors from the MISO / MOSI lines to the Data line –
http://www.nvlsi.no/index_popup.cfm?obj … 4&prop=354
It would seem possible to thus take advantage of the AVR’s hardware SPI to do all the bit shifting, freeing the processor for other tasks.
Though with the timing specs listed in the datasheet, I don’t think that it would be possible to send the data quicker than 1mhz to the internal FIFO - as I was originally thinking that you could use the AVR SPI at 4 or 8 mhz and fill up the transmit buffer quickly, if need be.
Could the second channel’s Clk2 and Dout2 be connected to the same SPI bus as well, or does it need to be separate?
By bit banging all the lines, is it possible to receive data on the two channels at the full 1mbps rate?
Ok, so it is a bit simpler than i thought… my bad :oops:
i’d expect having the high-value resistors there would affect signal integrity to some degree, though… probably best to have the SPI traces fairly well protected & short in such a case…