Prosthesis Using ADS1298

Hi Ali,

I recall that post regarding the ADS1298.  What is your confusion about the SPI interface?  For EEG/EMG, you may need additional gain - the INA333 may be an option for you as an input stage to the ADS1298. 

On the Mentor Graphics question, we did the bulk of the ADS1298ECGFE-PDK development in a different design environment - we could certainly pass along the files to you, but we would not be able to directly support your efforts in Mentor as a design database for your project.  Are you looking for a full design transfer or simply schematic symbols and PCB footprints?

Sir,

I have learned through the data sheet that the SCLK needs to be synchronized with the micro-controller, inorder to recieve and send data. Is that right? and i need to to connect my DRDY to interrupt. Thus deciding when to receive and when to send data. And my serial pin to DIN.Now the problems am facing are:

1. My output comes out through DOUT? or GIOP? if i have to run it in a continuous mode, then reading from DOUT will result in data loss. Can you please explain how i can receive my result from GIOP.

2. Can i use OPCODES in this setup? and how do i access registers of ADS as micro shall only access its own registers. Can you give me sample code for- accessing registers and writing values to them. Any example may work. (Am currently working on 89c51, and AVR)

Thank you for your help

Regards Ali

Hi Ali,

I'm sorry for the delay here - the ADS1298 is essentially an SPI slave device.  The Serial Peripheral Interface protocol is full duplex - the transmit/receive to/from slave/master happen at the same time.  You should not have to worry about GPIO or 'bit-banging' the interface to the ADS1298.

There are both DIN and DOUT pins.  The transfers to/from the ADS1298 happen simultaneously.  Your 89c51 probably has pins labeled as MISO and MOSI or SOMI and SIMO, these are the DIN/DOUT lines from your processor.  The Master SPI device (your processor) sends the necessary OpCodes to communicate with the ADS1298 through MOSI to DIN on the ADS1298.  The ADS1298 then responds through its DOUT ( to your MISO) with register content data, conversion data - depends on the OpCode sent.

Look over the Design Notes tab at the top of the Precision Data Converter forum - there are a few code examples there I believe that might help you get started.