Data converters

Data converters forum

State
Locked Locked
Replies 4 replies
Subscribers 45 subscribers
Views 622 views
Users 0 members are here

Support feedback

Options

Options

Related

ADS8688: Problem in received data from SDO

khlood Amin

Prodigy 30 points

Part Number: ADS8688

I have a problem in data received from Ads8688 , when i try to read register AUTO_SEQ_EN for example i always get the default value "0xFF" , i edit the sequence and read it tagain and i still get the same reading , this happen with all the registers

The frame i send to read = 0x02000000

The frame i send to write = 0x03550000

over 5 years ago

0 Dale Li over 5 years ago

TI__Mastermind 46055 points

Hi khlood Amin,

Can you please provide timing plot(/CS,SCLK,SDI and SDO) with an oscilloscope for register writing and reading? Could you get correct conversion data without register writing and reading? this can demonstrate if your SPI timing is correct.

Thanks&regards,

Dale

0 khlood Amin over 5 years ago in reply to Dale Li

Prodigy 30 points

This is a screenshot from scope , green line is the MOSI , yellow is data and blue is the MISO

0 khlood Amin over 5 years ago in reply to Dale Li

Prodigy 30 points

Hi Dale Li,

I couldn't get correct conversion data it is always 0xFFFF

0 Dale Li over 5 years ago in reply to khlood Amin

TI__Mastermind 46055 points

Hi khlood,

I guess your yellow signal is SCLK not "Data". You are sending 0xC000 to ADC to select CH0 which is correct,

How about your /CS signal? can you show the timing plot with /CS,SCLK,SDI and SDO together in one frame?

Did your configure your SPI with CPOL = 0, CPHA = 1 or 0? looks like you are capturing data on the rising edge of SCLK?, right?

Thanks for clarification.

Regards,

Dale