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ADS1299: Data conversion modes

Part Number: ADS1299


Hi.

I am looking ways to synchronize data conversation from 3 ADS1299 on application level and there are some question about this.

I found that single-shot mode is very useful in this task, but reading documentation remain many question about it:

( ADS1299-x Low-Noise, 4-, 6-, 8-Channel, 24-Bit, Analog-to-Digital ; SBAS499C –JULY 2012–REVISED JANUARY 2017 )

1). In «9.4.5 Continuous Conversion Mode» documentation shows :

" When switching from Single-Shot mode to Continuous Conversion mode, bring the START signal low and back high or send a STOP command followed by a START command. This conversion mode is ideal for applications that require a fixed continuous stream of conversions results."

ok, let's read «9.4.6 Single-Shot Mode» about Single-shot mode:

"When switching from Continuous Conversion mode to Single-Shot mode, bring the START signal low and back high or send a STOP command followed by a START command. This conversion mode is ideal for applications that require non-standard or non-continuous data rates."

2). There are two modes:

«Read Data Continuous mode» - when data automatically shift to output registers before DRDY pulls low ("Tupdate")

«Read data by command» - when data shift to output register after RDATA command received ("The RDATA command loads the output shift register with the latest data when not in Read Data Continuous

mode." - dataheet)

And in both modes "To retrieve data from the device after the RDATAC/RDATA command is issued,make sure either the START pin is high or the START command is issued.".

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What will actually happen if I bring the START signal low and back high - I will switch to continious mode after trying restart conversation(single-shot mode) or device itslelf will switch from continious to single-shot mode no matter what writen if CONFIG4 (continious mode)? What influence of CONFIG4 single-shot bit if device switch modes itself after start/stop commands ?

Can I read completed conversation data in single-shot mode after restarting new one ? Is I really need START pin high to receive last data if data already loaded in output register (RDATAC) and DRDY was pulled low ?