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This commit is contained in:
ladyada 2025-05-13 09:47:18 -04:00
parent ebe00b224d
commit ee1082bd87
1 changed files with 13 additions and 8 deletions
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21
Adafruit_OPT4048.cpp
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@ -135,18 +135,25 @@ bool Adafruit_OPT4048::getChannelsRaw(uint32_t *ch0, uint32_t *ch1, uint32_t *ch
Serial.println();
for (uint8_t ch = 0; ch < 4; ch++) {
uint16_t msb = ((uint16_t)buf[4 * ch] << 8) | buf[4 * ch + 1];
uint16_t lsb = ((uint16_t)buf[4 * ch + 2] << 8) | buf[4 * ch + 3];
uint8_t exp = (msb >> 12) & 0x0F;
uint32_t mant = ((msb & 0x0FFF) << 8) | ((lsb >> 8) & 0xFF);
uint8_t exp = (uint16_t)buf[4 * ch] >> 4)
uint16_t msb = (((uint16_t)(buf[4 * ch] & 0xF)) << 8) | buf[4 * ch + 1];
uint16_t lsb = ((uint16_t)buf[4 * ch + 2]);
uint8_t counter = buf[4 * ch + 3] >> 4;
uint8_t crc = buf[4 * ch + 3] & 0xF;
uint32_t mant = ((uint32_t)msb << 8) | lsb;
// Debug output for each channel
Serial.print(F("DEBUG: CH"));
Serial.print(ch);
Serial.print(F(": MSB=0x"));
Serial.print(msb, HEX);
Serial.print(msb, HEX); dsd
Serial.print(F(", LSB=0x"));
Serial.print(lsb, HEX);
Serial.print(F(", count="));
Serial.print(counter);
Serial.print(F(", crc="));
Serial.print(crc);
Serial.print(F(", exp="));
Serial.print(exp);
Serial.print(F(", mant=0x"));
@ -155,8 +162,6 @@ bool Adafruit_OPT4048::getChannelsRaw(uint32_t *ch0, uint32_t *ch1, uint32_t *ch
// Convert to 20-bit mantissa << exponent format
// This is safe because the sensor only uses exponents 0-6 in actual measurements
// (even when auto-range mode (12) is enabled in the configuration register)
uint32_t code = mant << exp;
uint8_t crc = lsb & 0x0F;
// Implementing CRC check based on the formula from the datasheet:
// CRC bits for each channel:
@ -177,7 +182,7 @@ bool Adafruit_OPT4048::getChannelsRaw(uint32_t *ch0, uint32_t *ch1, uint32_t *ch
// Calculate each CRC bit according to the datasheet formula:
// Calculate bit 0 (x0):
// X[0]=XOR(EXPONENT_CH0[3:0],R[19:0],COUNTER_CHx[3:0])
//X[0]=XOR(EXPONENT_CH0[3:0],R[19:0],COUNTER_CHx[3:0])
x0 = 0;
// The COUNTER_CHx[3:0] is the CRC itself