pxt-calliope/libs/microbit/pins.ts
2016-05-16 16:24:44 -07:00

70 lines
2.6 KiB
TypeScript

/**
* Control currents in Pins for analog/digital signals, servos, i2c, ...
*/
//% color=351 weight=30
namespace pins {
/**
* Re-maps a number from one range to another. That is, a value of ``from low`` would get mapped to ``to low``, a value of ``from high`` to ``to high``, values in-between to values in-between, etc.
* @param value value to map in ranges
* @param fromLow the lower bound of the value's current range
* @param fromHigh the upper bound of the value's current range, eg: 1023
* @param toLow the lower bound of the value's target range
* @param toHigh the upper bound of the value's target range, eg: 4
*/
//% help=pins/map weight=3
//% blockId=math_map block="map %value|from low %fromLow|from high %fromHigh|to low %toLow|to high %toHigh"
export function map(value: number, fromLow: number, fromHigh: number, toLow: number, toHigh: number): number {
return ((value - fromLow) * (toHigh - toLow)) / (fromHigh - fromLow) + toLow;
}
/**
* Read one number from 7-bit I2C address.
*/
//% help=pins/i2c-read-number blockGap=8
//% blockId=pins_i2c_readnumber block="i2c read number|at address %address|of format %format=i2c_sizeof" weight=7
export function i2cReadNumber(address: number, format: NumberFormat): number {
let buf = pins.i2cReadBuffer(address, pins.sizeOf(format))
return buf.getNumber(format, 0)
}
/**
* Write one number to a 7-bit I2C address.
*/
//% help=pins/i2c-write-number
//% blockId=i2c_writenumber block="i2c write number|at address %address|with value %value|of format %format=i2c_sizeof" weight=6
export function i2cWriteNumber(address: number, value: number, format: NumberFormat): void {
let buf = createBuffer(pins.sizeOf(format))
buf.setNumber(format, 0, value)
pins.i2cWriteBuffer(address, buf)
}
/**
* Get the size in bytes of specified number format.
*/
//%
export function sizeOf(format: NumberFormat) {
switch (format) {
case NumberFormat.Int8LE:
case NumberFormat.UInt8LE:
case NumberFormat.Int8BE:
case NumberFormat.UInt8BE:
return 1;
case NumberFormat.Int16LE:
case NumberFormat.UInt16LE:
case NumberFormat.Int16BE:
case NumberFormat.UInt16BE:
return 2;
case NumberFormat.Int32LE:
case NumberFormat.Int32BE:
return 4;
}
return 0;
}
}
interface Buffer {
[index: number]: number;
// rest defined in buffer.cpp
}