zigbee-herdsman
Version:
An open source ZigBee gateway solution with node.js.
83 lines • 3.73 kB
JavaScript
;
/* v8 ignore start */
//--------------------------------------------------------------
// Define macros for handling 3-bit frame numbers modulo 8
Object.defineProperty(exports, "__esModule", { value: true });
exports.byteToBits = exports.lowHighBits = exports.lowHighBytes = exports.bit32 = exports.bit = exports.highLowToInt = exports.highByte = exports.lowByte = exports.highBits = exports.lowBits = exports.halCommonCrc16 = exports.withinRange = exports.inc8 = exports.mod8 = void 0;
/** mask to frame number modulus */
const mod8 = (n) => n & 7;
exports.mod8 = mod8;
/** increment in frame number modulus */
const inc8 = (n) => (0, exports.mod8)(n + 1);
exports.inc8 = inc8;
/** Return true if n is within the range lo through hi, computed (mod 8) */
const withinRange = (lo, n, hi) => (0, exports.mod8)(n - lo) <= (0, exports.mod8)(hi - lo);
exports.withinRange = withinRange;
//--------------------------------------------------------------
// CRC
/**
* Calculates 16-bit cyclic redundancy code (CITT CRC 16).
*
* Applies the standard CITT CRC 16 polynomial to a
* single byte. It should support being called first with an initial
* value, then repeatedly until all data is processed.
*
* @param newByte The new byte to be run through CRC.
* @param prevResult The previous CRC result.
* @returns The new CRC result.
*/
const halCommonCrc16 = (newByte, prevResult) => {
/*
* 16bit CRC notes:
* "CRC-CCITT"
* poly is g(X) = X^16 + X^12 + X^5 + 1 (0x1021)
* used in the FPGA (green boards and 15.4)
* initial remainder should be 0xFFFF
*/
prevResult = ((prevResult >> 8) & 0xffff) | ((prevResult << 8) & 0xffff);
prevResult ^= newByte;
prevResult ^= (prevResult & 0xff) >> 4;
prevResult ^= (((prevResult << 8) & 0xffff) << 4) & 0xffff;
prevResult ^= (((prevResult & 0xff) << 5) & 0xff) | (((((prevResult & 0xff) >> 3) & 0xffff) << 8) & 0xffff);
return prevResult;
};
exports.halCommonCrc16 = halCommonCrc16;
//--------------------------------------------------------------
// Byte manipulation
/** Returns the low bits of the 8-bit value 'n' as uint8_t. */
const lowBits = (n) => n & 0xf;
exports.lowBits = lowBits;
/** Returns the high bits of the 8-bit value 'n' as uint8_t. */
const highBits = (n) => (0, exports.lowBits)(n >> 4) & 0xf;
exports.highBits = highBits;
/** Returns the low byte of the 16-bit value 'n' as uint8_t. */
const lowByte = (n) => n & 0xff;
exports.lowByte = lowByte;
/** Returns the high byte of the 16-bit value 'n' as uint8_t. */
const highByte = (n) => (0, exports.lowByte)(n >> 8) & 0xff;
exports.highByte = highByte;
/** Returns the value built from the two uint8_t values high and low. */
const highLowToInt = (high, low) => ((high & 0xffff) << 8) + (low & 0xffff & 0xff);
exports.highLowToInt = highLowToInt;
/** Useful to reference a single bit of a byte. */
const bit = (x) => 1 << x;
exports.bit = bit;
/** Useful to reference a single bit of an uint32_t type. */
const bit32 = (x) => 1 << x;
exports.bit32 = bit32;
/** Returns both the low and high bytes (in that order) of the same 16-bit value 'n' as uint8_t. */
const lowHighBytes = (n) => [(0, exports.lowByte)(n), (0, exports.highByte)(n)];
exports.lowHighBytes = lowHighBytes;
/** Returns both the low and high bits (in that order) of the same 8-bit value 'n' as uint8_t. */
const lowHighBits = (n) => [(0, exports.lowBits)(n), (0, exports.highBits)(n)];
exports.lowHighBits = lowHighBits;
/**
* Get byte as an 8-bit string (`n` assumed of proper range).
* @param n
* @returns
*/
const byteToBits = (n) => {
return (n >>> 0).toString(2).padStart(8, "0");
};
exports.byteToBits = byteToBits;
//# sourceMappingURL=math.js.map