15
Rev. 0
APPENDIX A: THE SKETCHBOOK CONTENTS
Common modifications can be made by changing the
Setup Variables. The most common application changes
are listed below. After the variables are changed, the
sketch will need to be recompiled and uploaded to the
Linduino.
1. To change the number of ICs in the isoSPI network,
change the TOTAL_IC variable. A number between 1
and 4 should be entered. In an application that has 2
devices in the network the modified line will look like:
const uint8_t TOTAL_IC = 2;
2. Often an application may need to sample data at a rate
faster than the default 500ms (2Hz). To modify the loop/
sample rate the MEASUREMENT_LOOP_TIME variable
should be changed. The loop time must be entered in
milliseconds and should be a number larger than 20mS.
To change the loop rate to roughly 10 measurements
a second the loop rate should be changed to 100mS.
The modified line will look like:
const uint16_t MEASUREMENT_LOOP_TIME = 100;
3. It is possible to modify which measurements fall within
the loop during the Loop Measurements command. The
following list are the measurements that can be looped:
const uint8_t MEASURE_CELL = ENABLED;
// This is ENABLED or DISABLED
const uint8_t MEASURE_AUX = DISABLED;
// This is ENABLED or DISABLED
const uint8_t MEASURE_STAT = DISABLED;
//This is ENABLED or DISABLED
By default only a cell measurement is done, as noted by
MEASURE_CELL = ENABLED. What measurements are
made can be changed by setting what the Measure field
is equal to. To Measure Cells and the Status register
but not the AUX register, the variables would be setup
as shown below:
const uint8_t MEASURE_CELL = ENABLED;
// This is ENABLED or DISABLED
const uint8_t MEASURE_AUX = DISABLED;
// This is ENABLED or DISABLED
const uint8_t MEASURE_STAT = ENABLED;
//This is ENABLED or DISABLED
4. ADC conversion settings can also be modified in the
Setup Variables section. The default setup is to run the
ADC in ‘Normal’ mode, which has a 7kHz filter code;
in this mode the ADC_OPT bit is Disabled. Typical
choice for which cell to convert is ALL. Full ADC
conversion programming requires setting ADC_OPT,
ADC_CONVERSION_MODE, CELL_CH_TO_CONVERT,
AUX_CH_TO_CONVERT, and STAT_CH_TO_CONVERT.
These variables are programmed with constants listed
in the LTC68xy_daisy.h file. For simplicity they are also
listed below:
MD_422HZ_1KHZ
MD_27KHZ_14KHZ
MD_7KHZ_3KHZ
MD_26HZ_2KHZ
ADC_OPT_ENABLED
ADC_OPT_DISABLED
CELL_CH_ALL
CELL_CH_1and7
CELL_CH_2and8
CELL_CH_3and9
CELL_CH_4and10
CELL_CH_5and11
CELL_CH_6and12
To set the ADC to have a 1kHz filter corner the ADC_OPT
and ADC_CONVERSION_MODE variables would be
changed to:
ADC_OPT = ADC_OPT_ENABLED;
ADC_CONVERSION_MODE = MD_422HZ_1KHZ;
To convert only cells 2 and 8,
CELL_CH_TO_CONVERT = CELL_CH_2and8;
5. In another example, the user may wish to change the
undervoltage and overvoltage thresholds. Each number
is based on an LSB of 100 µV.
//Under Voltage and Over Voltage Thresholds
const uint16_t OV_THRESHOLD = 41000;
// Over voltage threshold ADC Code. LSB = 0.0001
const uint16_t UV_THRESHOLD = 30000;
// Under voltage threshold ADC Code. LSB = 0.0001