Teridian 71M6534H, Руководство пользователя

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71M6534H Demo Board User’s Manual
Page: 33 of 86
© 2005-2007 TERIDIAN Semiconductor Corporation
V2-0
1.10.2 IMPORTANT DEMO CODE MPU PARAMETERS
In the Demo Code, certain MPU
XRAM
parameters have been given fixed addresses in order to permit easy
external access. These variables can be read via the serial interface, as described in section 1.7.1, with the
)n$
command and written with the
)n=xx
command where n is the word address. Note that accumulation variables
are 64 bits long and are accessed with
)n$$
(read) and
)n=hh=ll
(write) in the case of accumulation variables.
Default values are the values assigned by the Demo Code on start-up.
All MPU Input Parameters are loaded by the MPU at startup and should not need adjustment during meter
calibration.
MPU Input Parameters for Metering
XRAM Word
Address
Default
Value
Name Description
0x00 433199
ITHRSHLDA
For each element, if
WSUM_X
or
VARSUM_X
of that element
exceeds
WCREEP_THR
, the sample values for that element are
not zeroed. Otherwise, the accumulators for Wh, VARh, and VAh
are not updated and the instantaneous value of IRMS for that
element is zeroed.
16
2 I0SQSUM
⋅ =
LSB
The default value is equivalent to 0.08A. Setting
ITHRSHLDA
to
zero disables creep control.
0x01 0
CONFIG
Bit 0: Sets VA calculation mode.
0: V
RMS
*A
RMS
1:
2 2
VAR W
+
Bit 1: Clears accumulators for Wh, VARh, and VAh. This bit
need not be reset.
0x02 764569660
PK_VTHR
When the voltage exceeds this value, bit 5 in the MPU status
word is set, and the MPU might choose to log a warning. Event
logs are not implemented in Demo Code.
16
2 V0SQSUM
⋅ =
LSB
The default value is equivalent to 20% above 240Vrms.
0x03 275652520
PK_ITHR
When the current exceeds this value, bit 6 in the MPU status
word is set, and the MPU might choose to log a warning. Event
logs are not implemented in Demo Code.
16
2 I0SQSUM
⋅ =
LSB
The default value is equivalent to 20% above 30A
RMS
.
0x04 0
Y_CAL_DEG0
RTC adjust, 100ppb. Read only at reset in demo code.
0x05 0
Y_CAL_DEG1
RTC adjust, linear by temperature, 10ppb* Δ T, in 0.1 ˚ C. Provided
for optional code.
0x06 0
Y_CAL_DEG2
RTC adjust, squared by temperature, 1ppb* Δ T
2
, in 0.1 ˚ C.
Provided for optional code.