How to integrate 3 tof sensors on openmv to output data at the same time. Currently, I can only output data from one sensor.
What are you trying to do? And… maybe this isn’t support by us right now?
I want to link 3 tof sensors on openmv and then output distance data
Maybe my difficulty is that I don’t know how to modify the program to make three sensors output data at the same time. Currently I can make one output. I refer to the manual of the sensor and it is theoretically possible.
Yeah, we’re not designed to handle 3. If you want to do that you need to setup 3 different sensor I2C addresses and/or use them on different I2C buses.
What you said is correct, so I was able to send you my code and handbook to see if you can help me
Because I have a problem with how openmv sets the I2C address, I hope you can help me
You need to provide some information on what you are doing in code.
ok,no problems.
Sorry for the late reply, I’m in Hong Kong.
Regarding my code, I uploaded it in the dialog box, and also attached the related handbook of the sensor I used for reference. Thanks
code：
from micropython import const
import ustruct
import time
import utime
import pyb
from pyb import Pin, Timer
import sensor, time, image
from machine import I2C, Pin
_IO_TIMEOUT = 1000
_SYSRANGE_START = const(0x00)
_EXTSUP_HV = const(0x89)
_MSRC_CONFIG = const(0x60)
_FINAL_RATE_RTN_LIMIT = const(0x44)
_SYSTEM_SEQUENCE = const(0x01)
_SPAD_REF_START = const(0x4f)
_SPAD_ENABLES = const(0xb0)
_REF_EN_START_SELECT = const(0xb6)
_SPAD_NUM_REQUESTED = const(0x4e)
_INTERRUPT_GPIO = const(0x0a)
_INTERRUPT_CLEAR = const(0x0b)
_GPIO_MUX_ACTIVE_HIGH = const(0x84)
_RESULT_INTERRUPT_STATUS = const(0x13)
_RESULT_RANGE_STATUS = const(0x14)
_OSC_CALIBRATE = const(0xf8)
_MEASURE_PERIOD = const(0x04)
lens_mm = 2.8 # Standard Lens.
average_head_height_mm = 232.0 # https://en.wikipedia.org/wiki/Human_head
image_height_pixels = 240.0 # QVGA
sensor_h_mm = 2.952 # For OV7725 sensor - see datasheet.
offest_mm = 100.0 # Offset fix...
class TimeoutError(RuntimeError):
pass
class VL53L0X:
def __init__(self, i2c, address=0x29):
self.i2c = i2c
self.address = address
self.init()
#self.xshut_pin = xshut_pin
self._started = False
def _registers(self, register, values=None, struct='B'):
if values is None:
size = ustruct.calcsize(struct)
data = self.i2c.readfrom_mem(self.address, register, size)
values = ustruct.unpack(struct, data)
return values
data = ustruct.pack(struct, *values)
self.i2c.writeto_mem(self.address, register, data)
def _register(self, register, value=None, struct='B'):
if value is None:
return self._registers(register, struct=struct)[0]
self._registers(register, (value,), struct=struct)
def _flag(self, register=0x00, bit=0, value=None):
data = self._register(register)
mask = 1 << bit
if value is None:
return bool(data & mask)
elif value:
data |= mask
else:
data &= ~mask
self._register(register, data)
def _config(self, *config):
for register, value in config:
self._register(register, value)
def init(self, power2v8=True):
self._flag(_EXTSUP_HV, 0, power2v8)
# I2C standard mode
self._config(
(0x88, 0x00),
(0x80, 0x01),
(0xff, 0x01),
(0x00, 0x00),
)
self._stop_variable = self._register(0x91)
self._config(
(0x00, 0x01),
(0xff, 0x00),
(0x80, 0x00),
)
# disable signal_rate_msrc and signal_rate_pre_range limit checks
self._flag(_MSRC_CONFIG, 1, True)
self._flag(_MSRC_CONFIG, 4, True)
# rate_limit = 0.25
self._register(_FINAL_RATE_RTN_LIMIT, int(0.25 * (1 << 7)),
struct='>H')
self._register(_SYSTEM_SEQUENCE, 0xff)
spad_count, is_aperture = self._spad_info()
spad_map = bytearray(self._registers(_SPAD_ENABLES, struct='6B'))
# set reference spads
self._config(
(0xff, 0x01),
(_SPAD_REF_START, 0x00),
(_SPAD_NUM_REQUESTED, 0x2c),
(0xff, 0x00),
(_REF_EN_START_SELECT, 0xb4),
)
spads_enabled = 0
for i in range(48):
if i < 12 and is_aperture or spads_enabled >= spad_count:
spad_map[i // 8] &= ~(1 << (i >> 2))
elif spad_map[i // 8] & (1 << (i >> 2)):
spads_enabled += 1
self._registers(_SPAD_ENABLES, spad_map, struct='6B')
self._config(
(0xff, 0x01),
(0x00, 0x00),
(0xff, 0x00),
(0x09, 0x00),
(0x10, 0x00),
(0x11, 0x00),
(0x24, 0x01),
(0x25, 0xFF),
(0x75, 0x00),
(0xFF, 0x01),
(0x4E, 0x2C),
(0x48, 0x00),
(0x30, 0x20),
(0xFF, 0x00),
(0x30, 0x09),
(0x54, 0x00),
(0x31, 0x04),
(0x32, 0x03),
(0x40, 0x83),
(0x46, 0x25),
(0x60, 0x00),
(0x27, 0x00),
(0x50, 0x06),
(0x51, 0x00),
(0x52, 0x96),
(0x56, 0x08),
(0x57, 0x30),
(0x61, 0x00),
(0x62, 0x00),
(0x64, 0x00),
(0x65, 0x00),
(0x66, 0xA0),
(0xFF, 0x01),
(0x22, 0x32),
(0x47, 0x14),
(0x49, 0xFF),
(0x4A, 0x00),
(0xFF, 0x00),
(0x7A, 0x0A),
(0x7B, 0x00),
(0x78, 0x21),
(0xFF, 0x01),
(0x23, 0x34),
(0x42, 0x00),
(0x44, 0xFF),
(0x45, 0x26),
(0x46, 0x05),
(0x40, 0x40),
(0x0E, 0x06),
(0x20, 0x1A),
(0x43, 0x40),
(0xFF, 0x00),
(0x34, 0x03),
(0x35, 0x44),
(0xFF, 0x01),
(0x31, 0x04),
(0x4B, 0x09),
(0x4C, 0x05),
(0x4D, 0x04),
(0xFF, 0x00),
(0x44, 0x00),
(0x45, 0x20),
(0x47, 0x08),
(0x48, 0x28),
(0x67, 0x00),
(0x70, 0x04),
(0x71, 0x01),
(0x72, 0xFE),
(0x76, 0x00),
(0x77, 0x00),
(0xFF, 0x01),
(0x0D, 0x01),
(0xFF, 0x00),
(0x80, 0x01),
(0x01, 0xF8),
(0xFF, 0x01),
(0x8E, 0x01),
(0x00, 0x01),
(0xFF, 0x00),
(0x80, 0x00),
)
self._register(_INTERRUPT_GPIO, 0x04)
self._flag(_GPIO_MUX_ACTIVE_HIGH, 4, False)
self._register(_INTERRUPT_CLEAR, 0x01)
# XXX Need to implement this.
#budget = self._timing_budget()
#self._register(_SYSTEM_SEQUENCE, 0xe8)
#self._timing_budget(budget)
self._register(_SYSTEM_SEQUENCE, 0x01)
self._calibrate(0x40)
self._register(_SYSTEM_SEQUENCE, 0x02)
self._calibrate(0x00)
self._register(_SYSTEM_SEQUENCE, 0xe8)
def _spad_info(self):
self._config(
(0x80, 0x01),
(0xff, 0x01),
(0x00, 0x00),
(0xff, 0x06),
)
self._flag(0x83, 3, True)
self._config(
(0xff, 0x07),
(0x81, 0x01),
(0x80, 0x01),
(0x94, 0x6b),
(0x83, 0x00),
)
for timeout in range(_IO_TIMEOUT):
if self._register(0x83):
break
utime.sleep_ms(1)
else:
raise TimeoutError()
self._config(
(0x83, 0x01),
)
value = self._register(0x92)
self._config(
(0x81, 0x00),
(0xff, 0x06),
)
self._flag(0x83, 3, False)
self._config(
(0xff, 0x01),
(0x00, 0x01),
(0xff, 0x00),
(0x80, 0x00),
)
count = value & 0x7f
is_aperture = bool(value & 0b10000000)
return count, is_aperture
def _calibrate(self, vhv_init_byte):
self._register(_SYSRANGE_START, 0x01 | vhv_init_byte)
for timeout in range(_IO_TIMEOUT):
if self._register(_RESULT_INTERRUPT_STATUS) & 0x07:
break
utime.sleep_ms(1)
else:
raise TimeoutError()
self._register(_INTERRUPT_CLEAR, 0x01)
self._register(_SYSRANGE_START, 0x00)
def start(self, period=0):
self._config(
(0x80, 0x01),
(0xFF, 0x01),
(0x00, 0x00),
(0x91, self._stop_variable),
(0x00, 0x01),
(0xFF, 0x00),
(0x80, 0x00),
)
if period:
oscilator = self._register(_OSC_CALIBRATE, struct='>H')
if oscilator:
period *= oscilator
self._register(_MEASURE_PERIOD, period, struct='>H')
self._register(_SYSRANGE_START, 0x04)
else:
self._register(_SYSRANGE_START, 0x02)
self._started = True
def stop(self):
self._register(_SYSRANGE_START, 0x01)
self._config(
(0xFF, 0x01),
(0x00, 0x00),
(0x91, self._stop_variable),
(0x00, 0x01),
(0xFF, 0x00),
)
self._started = False
def read(self):
if not self._started:
self._config(
(0x80, 0x01),
(0xFF, 0x01),
(0x00, 0x00),
(0x91, self._stop_variable),
(0x00, 0x01),
(0xFF, 0x00),
(0x80, 0x00),
(_SYSRANGE_START, 0x01),
)
for timeout in range(_IO_TIMEOUT):
if not self._register(_SYSRANGE_START) & 0x01:
break
utime.sleep_ms(1)
else:
raise TimeoutError()
for timeout in range(_IO_TIMEOUT):
if self._register(_RESULT_INTERRUPT_STATUS) & 0x07:
break
utime.sleep_ms(1)
else:
raise TimeoutError()
value = self._register(_RESULT_RANGE_STATUS + 10, struct='>H')
self._register(_INTERRUPT_CLEAR, 0x01)
return value
def rect_size_to_distance(r): # r == (x, y, w, h) -> r[3] == h
return ((lens_mm * average_head_height_mm * image_height_pixels) / (r[3] * sensor_h_mm)) - offest_mm
sensor.reset()
sensor.set_contrast(1)
sensor.set_gainceiling(16)
sensor.set_framesize(sensor.QVGA)
#sensor.set_pixformat(sensor.GRAYSCALE)
sensor.set_pixformat(sensor.RGB565)
face_cascade = image.HaarCascade("frontalface", stages=25)
print(face_cascade)
i2c = I2C(sda=pyb.Pin('P5'), scl=pyb.Pin('P4'), freq=400000)
#mysensor=VL53L0X(i2c)
#mysensor.start()
#new
sensor1 = VL53L0X(i2c, address=0x29) # 初始化传感器1
#sensor2 = VL53L0X(i2c, address=0x30) # 初始化传感器2
#sensor3 = VL53L0X(i2c, address=0x31) # 初始化传感器3
sensor1.start()
#sensor2.start()
#sensor3.start()
#new
#now = time.time()
now = time.ticks_ms()
clock = time.clock()
clock.tick()
while (True):
clock.tick()
for i in range(0,5000):
img = sensor.snapshot()
objects = img.find_features(face_cascade, threshold=0.75, scale_factor=1.25)
#print(mysensor.read(),time.ticks_diff(time.ticks_ms(),now))
print(sensor1.read(),time.ticks_diff(time.ticks_ms(),now))
#print(sensor2.read(),time.ticks_diff(time.ticks_ms(),now))
#print(sensor3.read(),time.ticks_diff(time.ticks_ms(),now))
for i in range(len(objects)):
img.draw_rectangle(objects[i])
img.draw_string(objects[i][0] - 16, objects[i][1] - 16, "Distance %d mm" % rect_size_to_distance(objects[i]))
clock.tick()
The above is all the code. I have problems with address conflicts and how to modify them. I hope to get help.
handbook details：
I2C only allows one address-per-device so you have to make sure each I2C device has a unique address. The default address for the VL53L0X is 0x29 but you can change this in software.
To set the new address you can do it one of two ways. During initialization, instead of calling lox.begin(), call lox.begin(0x30) to set the address to 0x30. Or you can, later, call lox.setAddress(0x30) at any time.
The good news is its easy to change, the annoying part is each other sensor has to be in shutdown. You can shutdown each sensor by wiring up to the XSHUT pin to a microcontroller pin. Then perform something like this pseudo-code:
1.Reset all sensors by setting all of their XSHUT pins low for delay(10), then set all XSHUT high to bring out of reset
2.Keep sensor #1 awake by keeping XSHUT pin high
Put all other sensors into shutdown by pulling XSHUT pins low
3.Initialize sensor #1 with lox.begin(new_i2c_address) Pick any number but 0x29 and it must be under 0x7F. Going with 0x30 to 0x3F is probably OK.
4.Keep sensor #1 awake, and now bring sensor #2 out of reset by setting its XSHUT pin high.
5.Initialize sensor #2 with lox.begin(new_i2c_address) Pick any number but 0x29
and whatever you set the first sensor to
7.Repeat for each sensor, turning each one on, setting a unique address.
Note you must do this every time you turn on the power, the addresses are not permanent!
I’m sorry, since you know what to do given the handbook… what exactly do you need help with?
Although I found the relevant manual, I don’t know how to modify the code according to the syntax of openmv
Uh, it looks like you wrote the whole driver already in python?
You just need to use the pyb or machine module then to control the xhutdown pin.
Yeah… I mean, you have all the elements already in that script. I can provide help support for particular problems… however, you’re asking a very generic - “write my code for me” request. I cannot do that. If you find an issue that you aren’t able to solve after checking the documentation then I can help.
I wrote the above program in Openmv IDE. I hope you can help me find out the problems with xshut and modify it based on the handbook and your familiarity with openmv.
I’m not familiar with this and don’t know how to modify it, because I failed to modify it many times.
So I hope you can help me with the xshut problem
Really thank you.
Here’s how you control a pin: class Pin – control I/O pins — MicroPython 1.20 documentation
I cannot provide help support to write your code for you.