7 Revision History

Revision E - 06/2025


Document	Metrology library version v3.3.00. Apparent energy has been integrated as a source for metrology pulses. The Metrology Interface Definition section provides detailed information regarding the sizes and addresses of the register blocks. Updated Index and added Address column in the following tables: Table 3-2, Table 3-4, Table 3-5, and Table 3-6. Added Reset Value = 0 in all Registers. Updated start address in Metrology Status Registers, Accumulated Output Quantities, and Harmonic Analysis Output Quantities sections. Added new control registers S_K_t, CREEP_THRESHOLD_S, and POWER_OFFSET_S. The control register FEATURE_CTRL now includes a new flag, CREEP_S_EN, and the flag, SYNCH, changed the name from “Active Voltage Channel Selection” to “Dominant Voltage Channel Selection”. The control register PULSEx_CTRL has been modified to support the new functionalities related to apparent power pulsing capabilities. The control register POWER_OFFSET_CTRL now includes a new flag, S_OFFSET_PUL. Added Warning in HARMONIC_CONTROL, CAL_M_Ix, and CAL_M_Vx registers. The status register STATE_FLAG now includes a new flag, CREEP_DET_S, and the flag, TIMING_Vx, changed the name from “Active Voltage Channel” to “Dominant Voltage Channel”. The status register FREQ changed the name from “Active Line Voltage Fundamental Harmonic Frequency” to “Dominant Line Voltage Fundamental Harmonic Frequency”. Added Note in FREQ, and FREQ_Vx registers. Added an example for calculating the phase shift between voltages by applying the Law of Cosines in V_AB/V_BC/V_CA/V_AB_F/V_BC_F/V_CA_F register. Added VAh unit in ACC_T0, ACC_T1, and ACC_T2 in Table 3-5 and in ACC_T0/ACC_T1/ACC_T2 register. Changed sQ13.8 by sQ13.18 in Harmonic Analysis Output Quantities section. Updated the first paragraph in THD section. Updated Energy/Quadergy, and Vector Power Quantities sections. Added Average Apparent Power section.

Revision D - 12/2024


Document	Metrology library version v3.2.00. The library is able to compute up to 31 harmonic orders simultaneously. Functionality in FEATURE_CTRL0 and FEATURE_CTRL1 has been unified in FEATURE_CTRL0. FEATURE_CTRL1 was renamed to HARMONIC_CTRL. This register is used to enable the harmonic computation and for selecting the desired harmonics orders to be calculated. STATE_FLAG.HARMONIC_m_CONF[7:0] field was removed. HARMONIC output registers increased to 434 registers. The format changes. The values are not scaled with K_I_x and K_V_x registers. PU (Pull-Up) and OPD (Open-Drain) features removed from pulse control registers, as these functionalities are not available while under PWM peripheral control. Added a protection mechanism to avoid the issue that sometimes happened when the library was incorrectly configured to pulse all the energy being applied. The improper configuration occurred when the configured meter constants and pulse widths generated a pulse rate not supported, when applying energies above a threshold. The effect was that sometimes the library was not working properly, affecting the accuracy of the measurements. In previous version, the metrology library disabled the watchdogs. Now the watchdog control register is not written.

Rev C - 03/2024


Document	Metrology library version v3.1.02. Pulse algorithm changed to support testing inter-harmonics in the current circuits (burst fired waveform test, as defined in IEC62052-11:2021) using the pulses. Added counters for the number of pulses issued in the three pulse outputs. The counters are shown in the status registers 25, 26 and 27. Corrected a bug that in certain circumstances could generate unexpected pulses when transitioning from a high pulse rate to a very low or zero pulse rate. Included a clarification regarding the maximum metrology pulse rate.

Rev B - 10/2023


Document	Changed name of document from “Microchip PIC32CXMTx Metrology Data Sheet” to “PIC32CXMTx Metrology Reference Guide”. Metrology library version v3.1.00. Metrology pulses peripheral clock rate increased to 7.424 MHz. Pulse algorithm improved. Bug affecting the frequency measurements corrected. In previous versions, the frequency of the non-dominant phases was not accurate. Maximum metrology pulse rate increased to 1800 pulses/sec.

Rev A - 12/2022


Document	Initial release. Metrology library version v3.0.0b.

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