pxt-calliope/docs/reference/pins/i2c-read-number.md
Galen Nickel 985ad3d8e3 Add and update I2C topics (#602)
* Add and update I2C topics

* Throw in some edits for the serial buffer apis

* Add an example to serial read buffer
2017-12-11 22:34:33 -08:00

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# I2C Read Number
Read one number from an I2C address using a specified number format.
```sig
pins.i2cReadNumber(0, NumberFormat.Int8LE, false);
```
### ~hint
**Simulator**
This function needs real hardware to work with. It's not supported in the simulator.
### ~
## Parameters
* **address**: the 7-bit I2C address of the device you want to read a number from.
* **format**: the [NumberFormat](/types/buffer/number-format) of the number value to read.
* **repeated**: repeated start, true - don't send stop at end.
* **repeated**: if `true`, a [repeated start condition](http://www.i2c-bus.org/repeated-start-condition/) is set to help make sure the number is read from the device with out an interruption. If set to `false` (the default), the number is read without setting a start condition more than once.
## Returns
* a number from the device with the [NumberFormat](/types/buffer/number-format) you asked for.
## Example
The following example reads a number in big-endian, 16-bit, unsigned integer
format from the 7-bit I2C address `32`.
Read a number from the device at a 7-bit I2C address as a 16-bit number. The `16`, big-endian, and integer chosen for the format.
```blocks
pins.i2cReadNumber(32, NumberFormat.UInt16BE, false);
```
## See also
[What's I2C?](http://www.i2c-bus.org/), [number format](/types/buffer/number-format)