Andy, sofar I know the Master must pull the bus high with a pull-up
resistor
------ Original Message ------
From: "andy pugh" <bodge...@gmail.com>
To: "Enhanced Machine Controller (EMC)"
<emc-users@lists.sourceforge.net>
Sent: 2018-12-17 13:09:51
Subject: [Emc-users] SPI
Not as on-topic as I would like, but I suspect that some of you here
might know something useful.
I am trying to interface an ADS1256 board to an Arduino.
https://www.ebay.co.uk/itm/19242863594
Sometimes it almost works...
It will often sit there reading all-zeros then suddenly appear to
work, to an extent. But I don't seem to be able to configure it for
single-ended so suspect that the programming instructions are not
getting through.
The fact that the data output comes and goes makes me suspect that the
SPI comms is iffy.
The connection runs via the IO pins of an Arduino Nano,rather than
using the ICSP connector.
If I touch the ICSP connector on the Nano with my finger then the data
switches to 0xFFFFFF
So, I am wondering if the SPI bus needs to be terminated or something?
Also, the board has 100 Ohm resistors in series with all digital IO,
but the ADS1256 data sheet only shows 100R resisitors on the input
channels. Is this likely to be worth changing?
I have used other SPI devices with the Nano, and have not had these
problems.
I have also tried with a full-size Arduino, with equally limited
success.
Any tips for robustification of SPI comms?
--
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
