interface module

class interface.Singleton[source]

Bases: type

class interface.Interface(timeout=1.0, **kwargs)[source]

Bases: object

Communications library.

This class contains methods that can be used to interact with the hardware.

Initialization does the following

  • connects to tty device
  • loads calibration values.
Arguments Description
timeout serial port read timeout. default = 1s
>>> I = Interface(2.0)
>>> print I
<interface.Interface instance at 0xb6c0cac>

Once you have instantiated this class, its various methods will allow access to all the features built into the device.

I2C = None

Sub-Instance I2C of the Interface library contains methods to access devices connected to the I2C port.

example::
>>> I.I2C.start(self.ADDRESS,0) #writing mode
>>> I.I2C.send(0x01)
>>> I.I2C.stop()

See also

I2C for complete documentation

SPI = None

Sub-Instance SPI of the Interface library contains methods to access devices connected to the SPI port.

example::
>>> I=Interface()
>>> I.SPI.start('CS1')
>>> I.SPI.send16(0xAAFF)
>>> print I.SPI.send16(0xFFFF)
some number

See also

SPI for complete documentation

capture1(ch, ns, tg)[source]

Blocking call that fetches an oscilloscope trace from the specified input channel

Arguments  
ch Channel to select as input. [‘CH1’..’CH9’,‘5V’,’PCS’,‘9V’,’IN1’,’SEN’]
ns Number of samples to fetch. Maximum 3200
tg Timegap between samples in microseconds
alternate text

A sine wave captured and plotted.

Example

>>> from pylab import *
>>> I=interface.Interface()
>>> x,y = I.capture1('CH1',3200,1)
>>> plot(x,y)
>>> show()
Returns:Arrays X(timestamps),Y(Corresponding Voltage values)
capture2(ns, tg)[source]

Blocking call that fetches oscilloscope traces from CH1,CH2

Arguments  
ns Number of samples to fetch. Maximum 1600
tg Timegap between samples in microseconds
alternate text

Two sine waves captured and plotted.

Example

>>> from pylab import *
>>> I=interface.Interface()
>>> x,y1,y2 = I.capture2(1600,1.25)
>>> plot(x,y1)                          
>>> plot(x,y2)                          
>>> show()                              
Returns:Arrays X(timestamps),Y1(Voltage at CH1),Y2(Voltage at CH2)
capture4(ns, tg)[source]

Blocking call that fetches oscilloscope traces from CH1,CH2,CH3,CH4

Arguments  
ns Number of samples to fetch. Maximum 800
tg Timegap between samples in microseconds. Minimum 1.75uS
alternate text

Four traces captured and plotted.

Example

>>> from pylab import *
>>> I=interface.Interface()
>>> x,y1,y2,y3,y4 = I.capture4(800,1.75)
>>> plot(x,y1)                          
>>> plot(x,y2)                          
>>> plot(x,y3)                          
>>> plot(x,y4)                          
>>> show()                              
Returns:Arrays X(timestamps),Y1(Voltage at CH1),Y2(Voltage at CH2),Y3(Voltage at CH3),Y4(Voltage at CH4)
capture_traces(num, samples, tg, channel_one_input='CH1', CH123SA=0, **kwargs)[source]

Instruct the ADC to start sampling. use fetch_trace to retrieve the data

Arguments  
num Channels to acquire. 1/2/4
samples Total points to store per channel. Maximum 3200 total.
tg Timegap between two successive samples (in uSec)
channel_one_input map channel 1 to ‘CH1’ ... ‘CH9’
**kwargs  
  • trigger
Whether or not to trigger the oscilloscope based on the voltage level set by configure_trigger
alternate text

Transient response of an Inductor and Capacitor in series

The following example demonstrates how to use this function to record active events.

  • Connect a capacitor and an Inductor in series.
  • Connect CH1 to the spare leg of the inductor. Also Connect OD1 to this point
  • Connect CH2 to the junction between the capacitor and the inductor
  • connect the spare leg of the capacitor to GND( ground )
  • set OD1 initially high using set_state(OD1=1)
>>> I.set_state(OD1=1)  #Turn on OD1
>>> time.sleep(0.5)     #Arbitrary delay to wait for stabilization
>>> I.capture_traces(2,800,2,trigger=False)     #Start acquiring data (2 channels,800 samples, 2microsecond intervals)
>>> I.set_state(OD1=0)  #Turn off OD1. This must occur immediately after the previous line was executed.
>>> time.sleep(800*2*1e-6)      #Minimum interval to wait for completion of data acquisition. samples*timegap*(convert to Seconds)
>>> x,CH1=I.fetch_trace(1)
>>> x,CH2=I.fetch_trace(2)
>>> plot(x,CH1-CH2)     #Voltage across the inductor                            
>>> plot(x,CH2)         ##Voltage across the capacitor          
>>> show()                              

The following events take place when the above snippet runs

  1. The oscilloscope starts storing voltages present at CH1 and CH2 every 2 microseconds
  2. The output OD1 was enabled, and this causes the voltages across the L and C to fluctuate
  3. The data from CH1 and CH2 was read into x,CH1,CH2
  4. Both traces were plotted in order to visualize the Transient response of series LC
Returns:nothing

See also

fetch_trace , osciloscope_progress , capture1 , capture2 , capture4

fetch_trace(channel_number)[source]

fetches a channel(1-4) captured by capture_traces called prior to this, and returns xaxis,yaxis

Arguments  
channel_number Any of the maximum of four channels that the oscilloscope captured. 1/2/3/4
Returns:time array,voltage array

See also

capture_traces , osciloscope_progress

oscilloscope_progress()[source]

returns the number of samples acquired by the capture routines, and the conversion_done status

Returns:conversion done,samples acquired
>>> I.start_capture(1,3200,2)
>>> print I.osciloscope_progress()
(0,46)
>>> time.sleep(3200*2e-6)
>>> print I.osciloscope_progress()
(1,3200)
configure_trigger(chan, level)[source]

configure trigger parameters for 10-bit capture commands The capture routines will wait till a rising edge of the input signal crosses the specified level. The trigger will timeout within 8mS, and capture routines will start regardless.

These settings will not be used if the trigger option in the capture routines are set to False

Arguments  
chan channel . 0,1,2 or 3 corresponding to the channels being recorded by the capture routines
level The voltage level that should trigger the capture sequence(in Volts)

Example

>>> I.configure_trigger(0,1.1)
>>> I.capture_traces(4,800,2)
>>> I.fetch_trace(1)  #Unless a timeout occured, the first point of this channel will be close to 1.1Volts
>>> I.fetch_trace(2)  #This channel was acquired simultaneously with channel 1, so it's triggered along with the first
set_gain(channel, gain)[source]

set the gain of the selected PGA

Arguments  
channel ‘CH1’,’CH2’,’CH3’,’CH4’,’CH5’,’CH6’,’CH7’,’CH8’,’CH9’,‘5V’,’PCS’,‘9V’
gain (0-7) -> (1x,2x,4x,5x,8x,10x,16x,32x)

Note

The gain value applied to a channel will result in better resolution for small amplitude signals.

However, values read using functions like get_average_voltage or capture_traces will not be 2x, or 4x times the input signal. These are calibrated to return accurate values of the original input signal.

>>> I.set_gain('CH1',7)  #gain set to 32x on CH1
write_dac(channel, n)[source]

writes a value(12 bit) to the DAC.

Arguments Description
channel

channel number.

  • 0 -> PVS1 (-5 to 5V)
  • 1 -> PVS2 (0-3V)
n value to set (0-4095)
Returns:nothing

Warning

n should be between 0 and 4095 for both channels. The output voltage will be scaled accordingly.

>>> I.write_dac(0,4095) # pvs1 set to 5Volts
>>> I.write_dac(0,4095) # pvs1 set to -5Volts

See also

set_pvs1 and set_pvs2

get_average_voltage(channel_name, sleep=0)[source]

Return the voltage on the selected channel

Arguments Description
channel_name ‘CH1’,’CH2’,’CH3’,’CH4’,’CH5’,’CH6’,’CH7’,’CH8’,’CH9’,‘5V’,’PCS’,‘9V’,’IN1’,’SEN’,’TEMP’
sleep read voltage in CPU sleep mode. not particularly useful.

Example:

>>> print I.get_average_voltage('CH4')
0.002
get_high_freq(pin)[source]

retrieves the frequency of the signal connected to ID1. >10MHz also good for lower frequencies, but avoid using it since the ADC cannot be used simultaneously. It shares a TIMER with the ADC.

The input frequency is fed to a 32 bit counter for a period of 100mS. The value of the counter at the end of 100mS is used to calculate the frequency.

See also

get_freq

Arguments  
pin The input pin to measure frequency from. ‘ID1’ , ‘ID2’, ‘ID3’, ‘ID4’, ‘LMETER’,’CH4’
Returns:frequency
get_freq(channel='ID1', timeout=0.1)[source]

Frequency measurement on IDx. Measures time taken for 16 rising edges of input signal. returns the frequency in Hertz

Arguments  
channel The input to measure frequency from. ‘ID1’ , ‘ID2’, ‘ID3’, ‘ID4’, ‘LMETER’,’CH4’
timeout This is a blocking call which will wait for one full wavelength before returning the calculated frequency. Use the timeout option if you’re unsure of the input signal. returns 0 if timed out
Return float:frequency
  • connect SQR1 to ID1
>>> I.set_sqr1(2000,500,1) # TODO: edit this function
>>> print I.get_freq('ID1')
4000.0
>>> print I.r2r_time('ID1')     #time between successive rising edges
0.00025
>>> print I.f2f_time('ID1') #time between successive falling edges
0.00025
>>> print I.pulse_time('ID1') #may detect a low pulse, or a high pulse. Whichever comes first
6.25e-05
>>> I.duty_cycle('ID1')         #returns wavelength, high time
(0.00025,6.25e-05)                      
r2r_time(channel='ID1', timeout=0.1)[source]

Returns the time interval between two rising edges of input signal on ID1

Arguments  
channel The input to measure time between two rising edges.’ID1’ , ‘ID2’, ‘ID3’, ‘ID4’, ‘LMETER’,’CH4’
timeout Use the timeout option if you’re unsure of the input signal time period. returns 0 if timed out
Return float:time between two rising edges of input signal

See also

timing_example

f2f_time(channel='ID1', timeout=0.1)[source]

Returns the time interval between two falling edges of input signal on ID1

Arguments  
channel The input to measure time between two falling edges. ‘ID1’ , ‘ID2’, ‘ID3’, ‘ID4’, ‘LMETER’,’CH4’
timeout Use the timeout option if you’re unsure of the input signal time period. returns 0 if timed out
Return float:time between two falling edges of input signal

See also

timing_example

DutyCycle(channel='ID1', timeout=0.1)[source]

duty cycle measurement on channel

returns wavelength(seconds), and length of first half of pulse(high time)

low time = (wavelength - high time)

Arguments  
channel The input pin to measure wavelength and high time. ‘ID1’ , ‘ID2’, ‘ID3’, ‘ID4’, ‘LMETER’,’CH4’
timeout Use the timeout option if you’re unsure of the input signal time period. returns 0 if timed out

:return : wavelength,duty cycle

See also

timing_example

MeasureInterval(channel1, channel2, edge1, edge2, timeout=0.1)[source]

Measures time intervals between two logic level changes on any two digital inputs(both can be the same)

For example, one can measure the time interval between the occurence of a rising edge on ID1, and a falling edge on ID3. If the returned time is negative, it simply means that the event corresponding to channel2 occurred first.

returns the calculated time

Arguments  
channel1 The input pin to measure first logic level change
channel1
The input pin to measure second logic level change
  • ‘ID1’ , ‘ID2’, ‘ID3’, ‘ID4’, ‘LMETER’,’CH4’
edge1
The type of level change to detect in order to start the timer
  • ‘rising’
  • ‘falling’
  • ‘four rising edges’
edge2
The type of level change to detect in order to stop the timer
  • ‘rising’
  • ‘falling’
  • ‘four rising edges’
timeout Use the timeout option if you’re unsure of the input signal time period. returns -1 if timed out

:return : time

See also

timing_example

pulse_time(channel='CH1', timeout=0.1)[source]

pulse time measurement on ID1 returns pulse length(s) of high pulse or low pulse. whichever occurs first

Arguments  
channel
The input pin to measure pulse width from.
  • ‘ID1’ , ‘ID2’, ‘ID3’, ‘ID4’, ‘LMETER’,’CH4’
timeout
Use the timeout option if you’re unsure of the input signal time period.
returns 0 if timed out
Return float:pulse width in seconds

See also

timing_example

setup_comparator(level=7, digital_filter=3)[source]

setup the voltage level and filtering on the analog comparator linked to CH4. It can then be used to directly estimate the frequency and other timing details of input analog waveforms on CH4

Arguments  
level voltage level for + reference of comparator [0-15]
digital_filter Level changes faster than 3 * cpu freq / (1<<digital_filter) will be ignored

See also

timing_example

start_one_channel_LA(trigger=1, channel='ID1', maximum_time=67, **args)[source]

start logging timestamps of rising/falling edges on ID1

Arguments  
trigger Bool . Enable edge trigger on ID1. use keyword argument edge=’rising’ or ‘falling’
channel ‘ID1’,...’LMETER’,’CH4’
maximum_time Total time to sample. If total time exceeds 67 seconds, a prescaler will be used in the reference clock
Returns:Nothing
"fetch_long_data_from_dma(total,1)" to retrieve data
The read data can be accessed from self.dchans
start_two_channel_LA(trigger=1, maximum_time=67)[source]

start logging timestamps of rising/falling edges on ID1,AD2

Arguments  
trigger Bool . Enable rising edge trigger on ID1
maximum_time Total time to sample. If total time exceeds 67 seconds, a prescaler will be used in the reference clock
"fetch_long_data_from_dma(points to read,1)" to get data acquired from channel 1
"fetch_long_data_from_dma(points to read,2)" to get data acquired from channel 2
The read data can be accessed from self.dchans[0 or 1]
start_four_channel_LA(trigger=1, maximum_time=0.001, mode=[1, 1, 1, 1], **args)[source]

Four channel Logic Analyzer. start logging timestamps from a 64MHz counter to record level changes on ID1,ID2,ID3,ID4.

Arguments  
trigger Bool . Enable rising edge trigger on ID1
maximum_time Maximum delay expected between two logic level changes. If total time exceeds 1 mS, a prescaler will be used in the reference clock However, this only refers to the maximum time between two successive level changes. If a delay larger than .26 S occurs, it will be truncated by modulo .26 S. If you need to record large intervals, try single channel/ two channel modes which use 32 bit counters capable of time interval up to 67 seconds.
mode

modes for each channel. Array with four elements default values: [1,1,1,1]

EVERY_SIXTEENTH_RISING_EDGE = 5 EVERY_FOURTH_RISING_EDGE = 4 EVERY_RISING_EDGE = 3 EVERY_FALLING_EDGE = 2 EVERY_EDGE = 1 DISABLED = 0

Returns:Nothing

See also

Use fetch_long_data_from_LA (points to read,x) to get data acquired from channel x. The read data can be accessed from dchans [x-1]

get_LA_initial_states()[source]

fetches the initial states before the logic analyser started

Returns:chan1 progress,chan2 progress,chan3 progress,chan4 progress,[ID1,ID2,ID3,ID4]. eg. [1,0,1,1]
fetch_int_data_from_LA(bytes, chan=1)[source]

fetches the data stored by DMA. integer address increments

Arguments  
bytes: number of readings(integers) to fetch
chan: channel number (1-4)
fetch_long_data_from_LA(bytes, chan=1)[source]

fetches the data stored by DMA. long address increments

Arguments  
bytes: number of readings(long integers) to fetch
chan: channel number (1,2)
fetch_LA_channels(trigchan=1)[source]

reads and stores the channels in self.dchans.

Arguments  
trigchan:
channel number which should be treated as a trigger. (1,2,3,4). Its first timestamp
is subtracted from the rest of the channels.
get_states()[source]

gets the state of the digital inputs. returns dictionary with keys ‘ID1’,’ID2’,’ID3’,’ID4’

>>> print get_states()
{'ID1': True, 'ID2': True, 'ID3': True, 'ID4': False}
get_state(input_id)[source]

returns the logic level on the specified input (ID1,ID2,ID3, or ID4)

Arguments Description
input_id

the input channel

  • ‘ID1’ -> state of ID1
  • ‘ID2’ -> state of ID2
  • ‘ID3’ -> state of ID3
  • ‘ID4’ -> state of ID4
>>> print I.get_state(I.ID1)
False
set_state(**kwargs)[source]

set the logic level on digital outputs OD1,OD2,SQR1,SQR2

Arguments  
**kwargs
OD1,OD2,SQR1,SQR2
states(0 or 1)
>>> I.get_state(OD1=1,OD2=0,SQR1=1,SQR2=0)
get_capacitor_range()[source]

Charges a capacitor connected to IN1 via a 20K resistor from a 3.3V source for a fixed interval Returns the capacitance calculated using the formula Vc = Vs(1-exp(-t/RC)) This function allows an estimation of the parameters to be used with the get_capacitance function.

get_capacitance(current_range, trim, Charge_Time)[source]

measures capacitance of component connected between IN1 and ground

Warning

Non standard arguments! Needs to be rewritten

Parameters:
  • current_range (int) – current range to use (0,1,2,3) ->(550uA,.55uA,5.5uA,55uA)
  • trim (int) – trimming the current range selected. set as 0
  • Charge_Time (int) – total time in microseconds that the current range will be activated before measuring the voltage across it.
Returns:

Voltage,Charging current used,Charging time, Capacitance

get_inductance()[source]

measure the value of the inductor connected to the Inductance measurement unit

Returns:inductance
read_flash(location)[source]

Reads 16 BYTES from the specified location

Arguments  
location The flash location(0 to 63) to read from .
Returns:a string of 16 characters read from the location
read_bulk_flash(bytes)[source]

Reads BYTES from the specified location

Arguments  
bytes Total bytes to read
Returns:a string of 16 characters read from the location
write_flash(location, string_to_write)[source]

write a 16 BYTE string to the selected location (0-63)

Arguments  
location The flash location(0 to 63) to write to.
string_to_write a string of 16 characters can be written to each location
write_bulk_flash(bytearray)[source]

write a byte array to the entire flash page. Erases any other data

Arguments  
bytearray Array to dump onto flash. Max size 1024 bytes
get_ctmu_voltage(channel, Crange, tgen=1)[source]
Returns:Voltage
get_temperature()[source]

return a voltage equivalent of the on-chip temperature

Returns:Voltage
send_address(c)[source]

Outputs an address through the second UART This is used to select which PIC1572 will listen to incoming data

Arguments  
address slave device address
Returns:nothing
set_sine1(frequency, register=0)[source]

Set the frequency of sine 1

Arguments  
frequency Frequency to set on wave generator #1 0MHz to 8MHz
register Frequency register to update. The wavegen has two different registers for storing the output frequency. These are used to quickly switch between the two registers for applications like frequency shift keying(FSK)
Returns:frequency
set_sine2(frequency, register=0)[source]

Set the frequency of sine 2

Arguments  
frequency Frequency to set on wave generator #1 0MHz to 8MHz
register Frequency register to update. The wavegen has two different registers for storing the output frequency. These are used to quickly switch between the two registers for applications like frequency shift keying(FSK)
Returns:frequency
set_sine_phase(phase)[source]

Set the phase difference between WG1 and WG2

Arguments  
phase Phase difference between WG1 and WG2 0-360
set_waveform_type(channel, waveform='sine')[source]
select_freq(channel, register)[source]
reload_waveform(channel=1, expr='sin(x)')[source]

set shade of WS2182 LED on PIC1572 1 RA2

Note

This function normalizes and shifts the input table to the full voltage scale of the wavegen

Arguments  
Channel Channel number. 1/2 for Sine1 or Sine2
expr A mathematical expression for the waveform. Supports sin,cos,tan,exp
set_pvs1(val)[source]

Set the voltage on PVS1 12-bit DAC... -5V to 5V

Arguments  
val Output voltage on PVS1. -5V to 5V
set_pvs2(val)[source]

Set the voltage on PVS2. Unbuffered for improved stability 12-bit DAC... -0 - 3.3V

Arguments  
val Output voltage on PVS2. 0-3.3V
set_pvs3(val)[source]

Set the voltage on PVS3 5-bit DAC... -3V to 3V

Arguments  
val Output voltage on PVS3. -3.3V to 3.3V
Returns:Actual value set on pvs3
set_pcs(val)[source]

Set programmable current source 5-bit DAC... 0-3.3mA

Arguments  
val Output current on PCS. 0 to 3.3mA. Subject to load resistance. Read voltage on PCS to check.
Returns:value attempted to set on pcs
setOnboardLED(R, G, B)[source]

set shade of WS2182 LED on PIC1572 1 RA2

Arguments  
R brightness of red colour 0-255
G brightness of green colour 0-255
B brightness of blue colour 0-255
WS2182B(col)[source]

set shade of WS2182 LED on SQR1

Arguments  
col array [R,G,B]
R brightness of red colour 0-255
G brightness of green colour 0-255
B brightness of blue colour 0-255
tune_wavegen(tune)[source]

Tune the oscillator frequency of PIC1572 (1). 100000->111111 : no change to minimum 000001->011111 : - to maximum

Arguments  
tune change in clock frequency. -32 to 31
fetch_buffer(starting_position=0, total_points=100)[source]
clear_buffer(starting_position, total_points)[source]

returns a section of the buffer

start_streaming(tg, channel='CH1')[source]

Instruct the ADC to start streaming 8-bit data. use stop_streaming to stop.

Arguments  
tg timegap. 250KHz clock
channel channel ‘CH1’... ‘CH9’,’IN1’,’SEN’
stop_streaming()[source]

Instruct the ADC to stop streaming data

sqr1(freq, duty_cycle)[source]

Set the frequency of sqr1

Arguments  
frequency Frequency
duty_cycle Percentage of high time
sqr2(freq, duty_cycle)[source]

Set the frequency of sqr2

Arguments  
frequency Frequency
duty_cycle Percentage of high time
set_sqrs(wavelength, phase, high_time1, high_time2, prescaler=1)[source]

Set the frequency of sqr1,sqr2, with phase shift

Arguments  
wavelength Number of 64Mhz/prescaler clock cycles per wave
phase Clock cycles between rising edges of SQR1 and SQR2
high time1 Clock cycles for which SQR1 must be HIGH
high time2 Clock cycles for which SQR2 must be HIGH
prescaler 0,1,2. Divides the 64Mhz clock by 8,64, or 256
sqr4_pulse(freq, h0, p1, h1, p2, h2, p3, h3)[source]

Output one set of phase correlated square pulses on SQR1,SQR2,OD1,OD2 .

Arguments  
freq Frequency in Hertz
h0 Duty Cycle for SQR1 (0-1)
p1 Phase shift for SQR2 (0-1)
h1 Duty Cycle for SQR2 (0-1)
p2 Phase shift for OD1 (0-1)
h2 Duty Cycle for OD1 (0-1)
p3 Phase shift for OD2 (0-1)
h3 Duty Cycle for OD2 (0-1)
sqr4_continuous(freq, h0, p1, h1, p2, h2, p3, h3)[source]

Initialize continuously running phase correlated square waves on SQR1,SQR2,OD1,OD2

Arguments  
freq Frequency in Hertz
h0 Duty Cycle for SQR1 (0-1)
p1 Phase shift for SQR2 (0-1)
h1 Duty Cycle for SQR2 (0-1)
p2 Phase shift for OD1 (0-1)
h2 Duty Cycle for OD1 (0-1)
p3 Phase shift for OD2 (0-1)
h3 Duty Cycle for OD2 (0-1)
map_reference_clock(scaler, *args)[source]

Map the internal oscillator output to SQR1,SQR2,OD1 or OD2 The output frequency is 128/(1<<scaler) MHz

scaler [0-15]

  • 0 -> 128MHz
  • 1 -> 64MHz
  • 2 -> 32MHz
  • 3 -> 16MHz
  • .
  • .
  • 15 ->128./32768 MHz

example:

>>> I.map_reference_clock(2,'sqr1','sqr2')

outputs 32 MHz on sqr1, sqr2 pins

read_program_address(address)[source]

Reads and returns the value stored at the specified address in program memory

Arguments  
address Address to read from. Refer to PIC24EP64GP204 programming manual
read_data_address(address)[source]

Reads and returns the value stored at the specified address in RAM

Arguments  
address Address to read from. Refer to PIC24EP64GP204 programming manual|
write_data_address(address, value)[source]

Writes a value to the specified address in RAM

Arguments  
address Address to write to. Refer to PIC24EP64GP204 programming manual|
servo(chan, angle)[source]

Output A PWM waveform on SQR1/SQR2 corresponding to the angle specified in the arguments. This is used to operate servo motors. Tested with 9G SG-90 Servo motor.

Arguments  
chan 1 or 2. Whether to use SQ1 or SQ2 to output the PWM waveform used by the servo
angle 0-180. Angle corresponding to which the PWM waveform is generated.
servo4(a1, a2, a3, a4)[source]

Operate Four servo motors independently using SQR1, SQR2, OD1, OD2. tested with SG-90 9G servos.

Arguments  
a1 Angle to set on Servo which uses SQR1 as PWM input. [0-180]
a2 Angle to set on Servo which uses SQR2 as PWM input. [0-180]
a3 Angle to set on Servo which uses OD1 as PWM input. [0-180]
a4 Angle to set on Servo which uses OD2 as PWM input. [0-180]
enableUartPassthrough(baudrate)[source]

All data received by the device is relayed to an external port(SCL[TX],SDA[RX]) after this function is called

If a period > .5 seconds elapses between two transmit/receive events, the device resets and resumes normal mode. This timeout feature has been implemented in lieu of a hard reset option. can be used to load programs into secondary microcontrollers with bootloaders such ATMEGA, and ESP8266

Arguments  
baudrate BAUD9600... BAUD1000000
estimateDistance()[source]

Read data from ultrasonic distance sensor HC-SR04/HC-SR05. Sensors must have separate trigger and output pins. First a 10uS pulse is output on OD1. Therefore OD1 must be connected to the TRIG pin on the sensor prior to use.

The sensor then outputs an electrical pulse whose width is equal to the time taken by the sound pulse to return to the source. Therefore its output pin must be connected to ID1 prior to usage.

The ultrasound sensor outputs a series of 8 sound pulses at 40KHz which corresponds to a time period of 25uS per pulse. These pulses reflect off of the nearest object in front of the sensor, and return to it. The time between sending and receiving of the pulse packet is used to estimate the distance. If the reflecting object is either too far away or absorbs sound, less than 8 pulses may be received, and this can cause a measurement error of 25uS which corresponds to 8mm.

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