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en-us_commands:reference:analogreadinit

analogReadInit()

analogReadInit() sets the sampling rate of the analog input module.

analogReadInit command operation flow

void analogReadInit(uint16_t sps)

Commands

Command Arguments Return Value Operation
analogReadInit(sps) uint16_t sps void Sets the sampling rate of the analog input module.

Example

void setup() {
  Serial.begin(115200);
 
  // Use autocomplete constants
  analogReadInit(IANALOG_SPS_250);  // Set the analog input module's sampling rate.
}
 
void loop() {
  for (uint8_t ch = 0; ch < 4; ch++) {
    Serial.print("CH");
    Serial.print(ch);
    Serial.print(" = ");
    Serial.println(analogRead(ch));  // Read the raw analog value of the specified channel.
  }
}

Precautions

  • Settings other than SPS, such as PGA, input MUX and Single-shot mode, are not changed.
  • Higher SPS reduces conversion wait time, but check for value fluctuations due to field wiring and signal noise.
  • The internal ADS1118 maximum RATE is 860 SPS. Since the same channel is converted twice, the maximum requested return target is 475 SPS.
  • analogReadInit(128) uses the nearest higher RATE of 250 SPS, rather than 256 SPS, which the ADS1118 does not provide.
  • SPI communication and function processing add time, so the actual measurement SPS may be lower than the target.
  • analogRead() converts the same channel twice to prevent channel-value displacement. Include both conversion times when calculating the total channel update time.

Built-in Commands in the Same Category

en-us_commands/reference/analogreadinit.txt · Last modified: by 127.0.0.1

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