Skip to content

reset by SCLK reset pattern while initializing #23

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
RadoMmm wants to merge 1 commit into
base: main
Choose a base branch
from
Open

reset by SCLK reset pattern while initializing #23

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
71 changes: 53 additions & 18 deletions src/ADS1256.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -48,24 +48,32 @@ ADS1256::ADS1256(const byte DRDY_pin, const byte RESET_pin, const byte SYNC_pin,
//Initialization
void ADS1256::InitializeADC()
{
//Chip select LOW
digitalWrite(_CS_pin, LOW);

//We do a manual chip reset on the ADS1256 - Datasheet Page 27/ RESET
if(_RESET_pin != 0)
{
digitalWrite(_RESET_pin, LOW);
delay(200);
digitalWrite(_RESET_pin, HIGH); //RESET is set to high
delay(1000);
}

//Sync pin is also treated if it is defined
if(_SYNC_pin != 0)
{
digitalWrite(_SYNC_pin, HIGH); //RESET is set to high
}

//Sync pin is also treated if it is defined. Needs to be done before resetByClk()
if (_SYNC_pin != 0)
{
digitalWrite(_SYNC_pin, HIGH); //SYNC is set to high
}

//Chip select LOW
digitalWrite(_CS_pin, LOW);

//We do a manual chip reset on the ADS1256 - Datasheet Page 27/ RESET
if (_RESET_pin != 0)
{
digitalWrite(_RESET_pin, LOW);
delay(200);
digitalWrite(_RESET_pin, HIGH); //RESET is set to high
delay(1000);
}
else
{ // for case RST signal is not available/defined
// needs to be done before SPI.begin() to be able to write to SCK pin
pinMode(SCK, OUTPUT);
resetByClk();
resetByClk(); // repeat for case of SCLK pattern corruption by interrupt
delay(100);
}

SPI.begin();

//Applying arbitrary default values to speed up the starting procedure if the user just want to get quick readouts
Expand Down Expand Up @@ -751,3 +759,30 @@ void ADS1256::updateMUX(uint8_t muxValue)
}


void ADS1256::resetByClk()
{
// REF: p7, Figure 2 - SCLK reset pattern
// Tclkin = 130 ns for fCLKIN = 7.68MHz

digitalWrite(_CS_pin, LOW);
digitalWrite(SCK, LOW);
delay(1);

digitalWrite(SCK, HIGH);
delayMicroseconds(52); //400 * Tclkin

digitalWrite(SCK, LOW);
delayMicroseconds(1); //5 * Tclkin; 1us is actually longer but seems to be tolerated

digitalWrite(SCK, HIGH);
delayMicroseconds(85); //650 * Tclkin

digitalWrite(SCK, LOW);
delayMicroseconds(1); //5 * Tclkin

digitalWrite(SCK, HIGH);
delayMicroseconds(150); //1150 * Tclkin

digitalWrite(SCK, LOW);
delay(10);
}
3 changes: 3 additions & 0 deletions src/ADS1256.h
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -156,6 +156,9 @@ void updateMUX(uint8_t muxValue);

void updateConversionParameter(); //Refresh the conversion parameter based on the PGA

void resetByClk(); // send SCLK reset pattern


float _VREF = 0; //Value of the reference voltage
float conversionParameter = 0; //PGA-dependent multiplier
//Pins
Expand Down