Analog Shield jumper & chip-select values

[scottcjordan]

Two questions... many thanks in advance:

1) Per https://www.digilentinc.com/Data/Products/TI-ANALOG-SHIELD/AnalogShield_rm_rev3.pdf, ​"The Analog-to-Digital input converter (ADC) and Digital-to-Analog output converter (DAC) both use the standard Arduino form factor SPI bus pins and use independent chip selects."  

Question: For those of us developing our own library variants, what are the CS numbers?  I am not seeing this documented.

Update: From the attached snippet of the schematic, and the likelihood that "CS" =  "SYNC" = "SYNCN" = "CSN" = "SS" among other possible nomenclature, is CS for the ADC header pin 3, and CS for the DAC header pin 6?  (Also see attached close-up of the Shield's header, which suggests pin 0 on P7 is pin 0 for the Arduino Uno at least.  Note the nomenclature is clear on the screen-printing next to the header: ADCCS and DACCS.)  

Update: Argh!  The schematic pin numbering is 1-based; the silk-screened header pin numbers on the Shield are 0-based! ...Really now, this all ought to be documented unambiguously and consistently.  SO... are the pin numbers for the chip selects for ADC and DAC 5 and 2, respectively, for the Uno?

 

2) From the same document, "The jumper needs to be set for whether the connected board uses IOREF, 3V3, or 5V0 for the I/O for the SPI interface."

 Question: Which setting is needed for which supported Arduino board?  

That is:

• For the chipKIT Uno32, the jumper should be ____________
• For the chipKIT UC32, the jumper should be ____________ 
• For the chipKIT Max32, the jumper should be ____________
• For the chipKIT WF32, the jumper should be ____________
• For the Arduino Uno, the jumper should be ____________
   
• As a bonus, suggestions for determining the correct jumper setting from a schematic would be really handy.  

[JColvin]

Hi scottcjordan,

For your first question, the Chip Select numbers are pin 2 for the ADC and pin 5 for the DAC. I was able to determine this by looking at the analogShield.h file contained in the library that is available for download on it's resource center and by looking at the Analog Shield silk screen. The schematic shows numbers 3 and 6 since it does not start at an index of "0" like the software does.

As for the second question; chipKIT boards all use 3.3V for their I/O voltage, and should correspondingly use the 3.3V jumper setting. An Arduino board operates at its own set voltage (either 5V or 3.3V), but you may use the IOREF pin, so that the Analog Shield appropriately uses the reference voltage the Arduino board inherently supplies.  Unforunately, there is no easy way to determine the correct jumper setting from the schematic of the Analog Shield because as a shield, it is restricted to the operating voltage of the microcontroller board that it is plugged into; making it up to the user to look for the operating voltage of the microcontroller. 

Let me know if you have any more questions.

Thanks,
JColvin

[scottcjordan]

Thank you, JColvin!  As per my updates to my original post, I eventually figured out pins 2 and 5.  I have now moved the jumper to IOREF.  My software is not yet working but this is one fundamental step towards getting it going.

Thanks again for your helpfulness.

[angelito310390@hotmail.com]

 

could provide me some simple example of CONVERTION alalogico and digital to analog to digital using a pwm . chipKIT have one card 32