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@Miceuz
Created August 8, 2016 11:10
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//the original code by Ted Meyers
//posted here: https://groups.google.com/d/msg/diyrovers/lc7NUZYuJOg/ICPrYNJGBgAJ
#include <Wire.h>
#define VL53L0X_REG_IDENTIFICATION_MODEL_ID 0xc0
#define VL53L0X_REG_IDENTIFICATION_REVISION_ID 0xc2
#define VL53L0X_REG_PRE_RANGE_CONFIG_VCSEL_PERIOD 0x50
#define VL53L0X_REG_FINAL_RANGE_CONFIG_VCSEL_PERIOD 0x70
#define VL53L0X_REG_SYSRANGE_START 0x00
#define VL53L0X_REG_RESULT_INTERRUPT_STATUS 0x13
#define VL53L0X_REG_RESULT_RANGE_STATUS 0x14
#define address 0x29
byte gbuf[16];
void setup() {
// put your setup code here, to run once:
Wire.begin(); // join i2c bus (address optional for master)
Serial.begin(9600); // start serial for output
Serial.println("VLX53LOX test started.");
}
void loop() {
Serial.println("----- START TEST ----");
test();
Serial.println("----- END TEST ----");
Serial.println("");
delay(4000);
}
void test() {
byte val1 = read_byte_data_at(VL53L0X_REG_IDENTIFICATION_REVISION_ID);
Serial.print("Revision ID: "); Serial.println(val1);
val1 = read_byte_data_at(VL53L0X_REG_IDENTIFICATION_MODEL_ID);
Serial.print("Device ID: "); Serial.println(val1);
val1 = read_byte_data_at(VL53L0X_REG_PRE_RANGE_CONFIG_VCSEL_PERIOD);
Serial.print("PRE_RANGE_CONFIG_VCSEL_PERIOD="); Serial.println(val1);
Serial.print(" decode: "); Serial.println(VL53L0X_decode_vcsel_period(val1));
val1 = read_byte_data_at(VL53L0X_REG_FINAL_RANGE_CONFIG_VCSEL_PERIOD);
Serial.print("FINAL_RANGE_CONFIG_VCSEL_PERIOD="); Serial.println(val1);
Serial.print(" decode: "); Serial.println(VL53L0X_decode_vcsel_period(val1));
write_byte_data_at(VL53L0X_REG_SYSRANGE_START, 0x01);
byte val = 0;
int cnt = 0;
while (cnt < 100) { // 1 second waiting time max
delay(10);
val = read_byte_data_at(VL53L0X_REG_RESULT_RANGE_STATUS);
if (val & 0x01) break;
cnt++;
}
if (val & 0x01) Serial.println("ready"); else Serial.println("not ready");
read_block_data_at(0x14, 12);
uint16_t acnt = makeuint16(gbuf[7], gbuf[6]);
uint16_t scnt = makeuint16(gbuf[9], gbuf[8]);
uint16_t dist = makeuint16(gbuf[11], gbuf[10]);
byte DeviceRangeStatusInternal = ((gbuf[0] & 0x78) >> 3);
Serial.print("ambient count: "); Serial.println(acnt);
Serial.print("signal count: "); Serial.println(scnt);
Serial.print("distance "); Serial.println(dist);
Serial.print("status: "); Serial.println(DeviceRangeStatusInternal);
}
uint16_t bswap(byte b[]) {
// Big Endian unsigned short to little endian unsigned short
uint16_t val = ((b[0] << 8) & b[1]);
return val;
}
uint16_t makeuint16(int lsb, int msb) {
return ((msb & 0xFF) << 8) | (lsb & 0xFF);
}
void write_byte_data(byte data) {
Wire.beginTransmission(address);
Wire.write(data);
Wire.endTransmission();
}
void write_byte_data_at(byte reg, byte data) {
// write data word at address and register
Wire.beginTransmission(address);
Wire.write(reg);
Wire.write(data);
Wire.endTransmission();
}
void write_word_data_at(byte reg, uint16_t data) {
// write data word at address and register
byte b0 = (data &0xFF);
byte b1 = ((data >> 8) && 0xFF);
Wire.beginTransmission(address);
Wire.write(reg);
Wire.write(b0);
Wire.write(b1);
Wire.endTransmission();
}
byte read_byte_data() {
Wire.requestFrom(address, 1);
while (Wire.available() < 1) delay(1);
byte b = Wire.read();
return b;
}
byte read_byte_data_at(byte reg) {
//write_byte_data((byte)0x00);
write_byte_data(reg);
Wire.requestFrom(address, 1);
while (Wire.available() < 1) delay(1);
byte b = Wire.read();
return b;
}
uint16_t read_word_data_at(byte reg) {
write_byte_data(reg);
Wire.requestFrom(address, 2);
while (Wire.available() < 2) delay(1);
gbuf[0] = Wire.read();
gbuf[1] = Wire.read();
return bswap(gbuf);
}
void read_block_data_at(byte reg, int sz) {
int i = 0;
write_byte_data(reg);
Wire.requestFrom(address, sz);
for (i=0; i<sz; i++) {
while (Wire.available() < 1) delay(1);
gbuf[i] = Wire.read();
}
}
uint16_t VL53L0X_decode_vcsel_period(short vcsel_period_reg) {
// Converts the encoded VCSEL period register value into the real
// period in PLL clocks
uint16_t vcsel_period_pclks = (vcsel_period_reg + 1) << 1;
return vcsel_period_pclks;
}
@Koepel
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Koepel commented Aug 9, 2017

Hi, did you know that there is no need to wait for something after a Wire.requestFrom() ? When the Wire.requestFrom() returns, the I2C transaction has completely finished and the received data is waiting in a buffer in the Wire library.
You can remove the while-loops and delay(1) after the calls to Wire.requestFrom().

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