- Thu Mar 23, 2017 6:43 am
#64130
Hi, sorry it’s not in ESP Basic but the process, locations and values should save you some time when writing your own. Not pretty – the first attempt at communicating, but it works.
On a side note: Does anyone know if you can chainge the gain on the fly between reads of different inputs without doing any dammage? I want to read the state of charging/discharging of two batteries. The voltage can be any scale, but the current is measured as voltage across a low value shunt and is likley to be quite small. I could do with reading 4V FSD on two pins and 0.512V FSD on the other two.
EDIT: It looks like you can without doing any dammage: http://e2e.ti.com/support/data_converte ... 3/t/378122
On a side note: Does anyone know if you can chainge the gain on the fly between reads of different inputs without doing any dammage? I want to read the state of charging/discharging of two batteries. The voltage can be any scale, but the current is measured as voltage across a low value shunt and is likley to be quite small. I could do with reading 4V FSD on two pins and 0.512V FSD on the other two.
EDIT: It looks like you can without doing any dammage: http://e2e.ti.com/support/data_converte ... 3/t/378122
Code: Select all
/* An exapmle of an ESP8266 reading an ADS1115 without a library.
4 single ended reads, single shot mode, 4.096V full scale deflection.
See data sheet for config settings and other functions. */
#include <Wire.h>
int config_MSB; //var for config read.
int config_LSB; //var for config read.
short val_AIN0; //var for AIN0 read.
short val_AIN1; //var for AIN1 read.
short val_AIN2; //var for AIN2 read.
short val_AIN3; //var for AIN3 read.
const float scale_factor = 4.096 / 32768; //4.096 = full scale voltage.
const int convert_delay = 100; // delay for ADS1115 to do ADC convertion.
void setup() {
Serial.begin(115200); //start Serial.
Wire.begin(4, 5); //start Wire and set SDA - SCL.
// Write config settings. //
Wire.beginTransmission(0x48); //start write to board 0x48 (address pin -> Gnd).
Wire.write(B00000001); //write move pointer to config register.
Wire.write(B11000011); //write MSB of config.
Wire.write(B10000011); //write LSB of config.
Wire.endTransmission(); //write end.
// Read config settings. //
Wire.beginTransmission(0x48); //start write to board 0x48 (address pin -> Gnd).
Wire.write(B00000001); //write move pointer to config register.
Wire.endTransmission(); //write end.
Wire.requestFrom(0x48, 2); //read request 2 bytes from board 0x48 (address pin -> Gnd).
config_MSB = Wire.read(); // store config byte.
config_LSB = Wire.read(); // store config byte.
Serial.println();
Serial.print(config_MSB, BIN); // print config byte.
Serial.print(" ");
Serial.print(config_LSB, BIN); // print config byte.
Serial.println();
}
void loop() {
Serial.print("Readings");
// Read AIN0 - convert - print - single shot mode //
Wire.beginTransmission(0x48); //start write to board 0x48 (address pin -> Gnd).
Wire.write(B00000001); //write move pointer to config register.
Wire.write(B11000011); //write MSB of config, bits [14:12] set for AIN0 single ended.
Wire.write(B10000011); //write LSB of config.
Wire.endTransmission(); //write end.
delay(convert_delay); // delay for ADS1115 to do ADC convertion.
Wire.beginTransmission(0x48); //start write to board 0x48 (address pin -> Gnd).
Wire.write(B00000000); //write move pointer to conversion register.
Wire.endTransmission(); //write end.
Wire.requestFrom(0x48, 2); //read request 2 bytes from board 0x48 (address pin -> Gnd).
val_AIN0 = Wire.read() << 8 | Wire.read(); //store read as 16 bit value.
Serial.println();
Serial.print("AIN0 = ");
Serial.print(val_AIN0 * scale_factor, DEC); //scale & print read value.
// Read AIN1 - convert - print - single shot mode //
Wire.beginTransmission(0x48); //start write to board 0x48 (address pin -> Gnd).
Wire.write(B00000001); //move pointer to config register.
Wire.write(B11010011); //write MSB of config, bits [14:12] set for AIN1 single ended.
Wire.write(B10000011); //write LSB of config.
Wire.endTransmission(); //write end.
delay(convert_delay); // delay for ADS1115 to do ADC convertion.
Wire.beginTransmission(0x48); //start comms with board 0x48.
Wire.write(B00000000); //write move pointer to conversion register.
Wire.endTransmission(); //write end.
Wire.requestFrom(0x48, 2); //read request 2 bytes from board 0x48 (address pin -> Gnd).
val_AIN1 = Wire.read() << 8 | Wire.read(); //store read as 16 bit value.
Serial.println();
Serial.print("AIN1 = ");
Serial.print(val_AIN1 * scale_factor, DEC); //scale & print read value
// Read AIN2 - convert - print - single shot mode //
Wire.beginTransmission(0x48); //start write to board 0x48 (address pin -> Gnd).
Wire.write(B00000001); //write move pointer to config register.
Wire.write(B11100011); //write MSB of config, bits [14:12] set for AIN2 single ended.
Wire.write(B10000011); //write LSB of config.
Wire.endTransmission(); //write end.
delay(convert_delay); // delay for ADS1115 to do ADC convertion.
Wire.beginTransmission(0x48); //read request 2 bytes from board 0x48 (address pin -> Gnd).
Wire.write(B00000000); //move pointer to conversion register.
Wire.endTransmission(); //write end.
Wire.requestFrom(0x48, 2); //read request 2 bytes from board 0x48 (address pin -> Gnd).
val_AIN2 = Wire.read() << 8 | Wire.read(); //store read as 16 bit value.
Serial.println();
Serial.print("AIN2 = ");
Serial.print(val_AIN2 * scale_factor, DEC); //scale & print read value
// Read AIN3 - convert - print - single shot mode //
Wire.beginTransmission(0x48); //start write to board 0x48 (address pin -> Gnd).
Wire.write(B00000001); //write move pointer to config register.
Wire.write(B11110011); //write MSB of config, bits [14:12] set for AIN3 single ended.
Wire.write(B10000011); //write LSB of config.
Wire.endTransmission(); //write end.
delay(convert_delay); // delay for ADS1115 to do ADC convertion.
Wire.beginTransmission(0x48); //start write to board 0x48 (address pin -> Gnd).
Wire.write(B00000000); //write move pointer to conversion register.
Wire.endTransmission(); //write end.
Wire.requestFrom(0x48, 2); //read request 2 bytes from board 0x48 (address pin -> Gnd).
val_AIN3 = Wire.read() << 8 | Wire.read(); //store read as 16 bit value.
Serial.println();
Serial.print("AIN3 = ");
Serial.print(val_AIN3 * scale_factor, DEC); //scale & print read value
delay(20000); //delay between reads.
Serial.println();
}
