Andy, Of course a scope here is your friend. If you don't have one do some simple tests. 1. Make sure /RESET and /PDWN are both pulled to +3.3V or 5V with a resistor. The data sheet says these are 5V tolerant to 6V. 2. Make sure the /CS signal is pulled low before you start clocking. 3. Program the Arduino w/o SPI and set each of the outputs MOSI and CLK to be Low and then high. Measure with a meter to make sure they match the spec sheet voltages. 4. But if you don't have a scope try each of the modes for SPI. 5. Forget about the A/D initially and program the General Purpose I/O pins to have values that you can check with a meter or read back the pins to verify you are addressing and sending data. John
> -----Original Message----- > From: andy pugh [mailto:bodge...@gmail.com] > Sent: December-17-18 7:27 AM > To: Bruce Layne > Cc: Enhanced Machine Controller (EMC) > Subject: Re: [Emc-users] SPI > > On Mon, 17 Dec 2018 at 15:06, Bruce Layne <linux...@thinkingdevices.com> > wrote: > > > Generally speaking, there are four modes of transmission > > > > Looking at http://www.ti.com/lit/ds/symlink/ads1256.pdf (figure 1) and > https://en.wikipedia.org/wiki/Serial_Peripheral_Interface I am not 100% > clear which mode is being described, but probably mode 1? > > > -- > atp > "A motorcycle is a bicycle with a pandemonium attachment and is designed > for the especial use of mechanical geniuses, daredevils and lunatics." > � George Fitch, Atlanta Constitution Newspaper, 1916 > > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
