defines.c

使用AVR单片机设计的单相电表设计程序.不使用专用电表芯片,直接用AVR单片机AD采样交流电压电流,计算电压电流有效值和有功功率及有功电度和功率因数.

/*****************************************************************************
*
* Atmel Corporation
*
* File              : Defines.c
* Compiler          : IAR EWAAVR 3.10C
* Revision          : $Revision: 1.31 $
* Date              : $Date: Friday, July 02, 2004 11:13:12 UTC $
* Updated by        : $Author: kmeyer $
*
* Support mail      : [e-mail]
*
* Supported devices : This example is written for the ATmega88. Firmware
*                     as such should fit in any other AVR with 8kB Flash.
*
* AppNote           : AVR465: Single-Phase Power/Energy Meter with
*                     Tamper Detection.
*
* Description       : This file includes definitions used by the main file.
*
****************************************************************************/

/////////////////////////////////////////////////////////////////////////////
//  D E F I N E S
/////////////////////////////////////////////////////////////////////////////

// Use internal voltage reference + external stabilising capacitors
#define ADC_VREF_TYPE 0xC0

// Masks for output signals
//
//  PORT | MASK | BIT7 | BIT6 | BIT5 | BIT4 | BIT3 | BIT2 | BIT1 | BIT0 |
//  -----+------+------+------+------+------+------+------+------+------+
//    B  | 0x03 |   0  |   0  |   0  |   0  |   0  |   0  |  EP  | DUTY |
//    C  | 0x18 |   0  |   0  |   0  |REVDIR| EARTH|   0  |   0  |   0  |
//    D  | 0xFC |  DPN |  DPP | GAIN | GAIN | GAIN | GAIN |   0  |   0  |
#define DUTY          0x01
#define EP            0x02
#define EARTH         0x08
#define REVDIR        0x10
#define DPP           0x40
#define DPN           0x80
#define DIRB          0x03
#define DIRC          0x18
#define DIRD          0xFC

// Gain stage control constants
#define	ADC0	      0
#define	ADC1	      1
#define LOW           0
#define	MEDIUM        1
#define HIGH          2

// Step up gain when amplitude of FILTERED signal drops below AMP_LO.
// Assuming 8.000x gain, the threshold may not be set higher than:
//
//  AMP_LO(max) = 255 * [(1023/2) / 8] = 16304d = 3FB0h
//
// Measurement results indicate 1% accuracy can be reached at amplitudes as
// low as 25, at unity power factor. Leaving some headroom for 0.5 power
// factor measurements, the recommended minimum is:
//
//  AMP_LO(min) = 255*50 = approx 3200h
#define AMP_LO        0x3200

// Step down gain when UNCONDITIONED data is below SAT_LO or above SAT_HI
#define SAT_LO        0x0007
#define SAT_HI        0x03F8

// Wait GAIN_HOLD samples after range switch before allowing new switch
#define GAIN_HOLD     480

// Starting current in amps: this should be no more than 0.002 x base current
#define I_MIN         0.002

// Power threshold in watts: disable tamper logic when active power below this
#define P_MIN         1.000

// Constant offset, which is added to sampled data. Should not be more than
// 1/2 LSB*255, typically OFFSET = 80h. Else transfer funtion may grow non-
// linear (especially at power factors other than 1).
#define OFFSET        0x80

// Flags
#define DISPLAY       0x01
#define GROGGY        0x02
#define KEY_PRESSED   0x04
#define CYCLE_FULL    0x08
#define MOREGAIN0     0x10
#define LESSGAIN0     0x20
#define MOREGAIN1     0x40
#define LESSGAIN1     0x80

// Number of samples that will be accumulated for measurements. Since measure-
// ments are based on a fixed time window, the accumulation cycle should be
// such that it fits an integer number of mains cycles. Otherwise, measurement
// results will fluctuate and create short-term variations. Even so, the
// effects can be completely removed by means of averaging the measurement
// results. No harm done in the long run, but may look strange and gives a
// false impression of poor accuracy.
//
// For compliancy with both 50Hz and 60Hz environments, the cycle length
// should be chosen such, that it can fit an integer number of both 50Hz and
// 60Hz signals. For example, cycle lengths of 200ms multiples are fine.
// Some suitable cycle lengths are as follows:
//
//    XTAL |   ADC | ADCCLK |  Sampling | S.R./Ch |  Cycle |    50Hz |    60Hz
//   [MHz] | Presc |   [Hz] | Rate [Hz] |    [Hz] | Length |  Cycles |  Cycles
//   ------+-------+--------+-----------+---------+--------+---------+--------
//   3.580 |   128 |  27965 | 2151.169  |  717.06 |   N*72 | N*5.021 | N*6.025
//   3.689 |   128 |  28800 | 2215.385  |  738.46 |   N*74 | N*5.010 | N*6.012
//   4.000 |   128 |  31250 | 2403.846  |  801.28 |   N*80 | N*4.999 | N*5.999
//    -"-  |   -"- |   -"-  |    -"-    |    -"-  |     80 |  4.9920 |  5.9904
//    -"-  |   -"- |   -"-  |    -"-    |    -"-  |    401 | 25.0225 | 30.0270
//   4.096 |   128 |  32000 | 2461.538  |  820.51 |   N*82 | N*5.000 | N*6.000
//   4.608 |   128 |  36000 | 2769.231  |  923.08 |   N*92 | N*4.983 | N*5.980
#define NMAX	401
#define NORM    1.0/NMAX

// This is the length of pulses DPP and DPN, measured in sampling periods.
// For example, DP_ON=241 at sampling rate 2403Hz results in pulse lengths
// of (241-1)/2403 = 0.100s.
#define DP_ON   241

// Polynome used in CRC calculations
#define	CRC_POLYNOME 0x8005