is it possible to use I2C bus devices with 16-bit register addresses ?

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#is it possible to use I2C bus devices with 16-bit register addresses ?

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kaxori 09/23/2024 02:14 PM

see => comment in i2c.toit

Writes the $bytes to the device at the given $register.

  The $register value must satisfy 0 <= $register < 256.
  This is a convenience method and equivalent to prepending the $register byte to $bytes
    and then calling $(write bytes).

kaxori 09/23/2024 02:25 PM

I am trying to use a VL6180X (Proximity and ambient light sensing (ALS) module).

floitsch 09/23/2024 02:26 PM

It's possible. I'm trying to find a driver that uses 16-bit registers.

floitsch 09/23/2024 02:28 PM

Can't find the driver.

kaxori 09/23/2024 02:28 PM

floitsch 09/23/2024 02:30 PM

What were the arguments for this call?

kaxori 09/23/2024 02:32 PM

i2c-read-reg_ i2c address reg size:
  #primitive.i2c.read-reg

may be the reg is meant to be only a byte wide. But the chip uses 16bit register addresses

floitsch 09/23/2024 02:33 PM

Basically you can't use read-reg directly. But as the command explains, you should be able to do read-address #[your-address] size

floitsch 09/23/2024 02:33 PM

Where #[your-address] consists of two bytes.

floitsch

What were the arguments for this call?

kaxori 09/23/2024 02:33 PM

print "registers_ : $(registers_.read-u8 0x00)"
print "registers_ : $(registers_.read-u8 0x0212)"

OPkaxori

 
print "registers_ : $(registers_.read-u8 0x00)"
print "registers_ : $(registers_.read-u8 0x0212)"

kaxori 09/23/2024 02:34 PM

2nd call causes the error

floitsch 09/23/2024 02:34 PM

I think you will need to work directly on the device instead of the registers.

floitsch 09/23/2024 02:36 PM

If you do device := bus.device ..., then you get an i2c.Device back which has the method 'read-address` method.

floitsch 09/23/2024 02:36 PM

https://libs.toit.io/i2c/class-Device#read-address(2%2C0%2C0%2C)

floitsch 09/23/2024 02:36 PM

just means that you don't have the utitility functions read-uint16 ,...

floitsch 09/23/2024 02:37 PM

Found the driver: https://github.com/jacobqvist/scd30/blob/main/src/driver.toit

scd30/src/driver.toit at main · jacobqvist/scd30

Contribute to jacobqvist/scd30 development by creating an account on GitHub.

floitsch 09/23/2024 02:38 PM

That driver just writes the command and then reads a certain number of bytes.
Not sure that would work with your sensor.

floitsch 09/23/2024 02:38 PM

But the read-address should.

kaxori 09/23/2024 03:38 PM

read-register16 reg bytes -> ByteArray:
    return device_.read-address #[reg>>8, reg] bytes

  write-register16 reg bytes/ByteArray:
    device_.write-address #[reg>>8, reg] bytes

Thank you - it works!

20 messages in total