Quick reference for the Renesas RA

Renesas Evaluation Kit for RA6M2 MCU Group

The Renesas EK-RA6M2 board.

Below is a quick reference for the Renesas RA boards. If it is your first time working with this board, it may be useful to get an overview of the microcontroller and the board:

Installing MicroPython

See the corresponding section of tutorial: Getting started with MicroPython on the Renesas RA. It also includes a troubleshooting subsection.

General board control

The MicroPython REPL is accessed via the USB serial port. Tab-completion is useful to find out what methods an object has. Paste mode (ctrl-E) is useful to paste a large slab of Python code into the REPL. Some of features are not implemented for Renesas RA boards yet, please refer to the tutorial for more details.

The machine module:

import machine

machine.freq()    # get the current frequency of the CPU

Following functions are supported:

machine.freq()
machine.reset()
machine.soft_reset()
machine.unique_id()

Following functions are not supported at the present:

machine.reset_cause()
machine.bootloader([value])
machine.disable_irq()
machine.enable_irq(state)
machine.freq([hz])
machine.idle()
machine.sleep()
machine.lightsleep()
machine.lightsleep([time_ms])
machine.deepsleep()
machine.deepsleep([time_ms])
machine.wake_reason()
machine.time_pulse_us(pin, pulse_level, timeout_us=1000000,/)
machine.bitstream(pin, encoding, timing, data, /)
machine.rng()

Delay and timing

Use the time module:

import time

time.sleep(1)           # sleep for 1 second
time.sleep_ms(500)      # sleep for 500 milliseconds
time.sleep_us(10)       # sleep for 10 microseconds
start = time.ticks_ms() # get value of millisecond counter
delta = time.ticks_diff(time.ticks_ms(), start) # compute time difference

Timers

The RA MCU’s system timer peripheral provides a global microsecond timebase and generates interrupts for it. The software timer is available currently and there are unlimited number of them (memory permitting). There is no need to specify the timer id (id=-1 is supported at the moment) as it will default to this.

Use the machine.Timer class:

from machine import Timer

tim = Timer(-1)
tim.init(period=5000, mode=Timer.ONE_SHOT, callback=lambda t:print(1))
tim.init(period=2000, mode=Timer.PERIODIC, callback=lambda t: print(2))
Following functions are not supported at the present::

Timer(id) # hardware timer is not supported.

Pins and GPIO

Use the machine.Pin class:

from machine import Pin

p0 = Pin('P000', Pin.OUT)      # create output pin on P000
p0.on()                        # set pin to "on" (high) level
p0.off()                       # set pin to "off" (low) level
p0.value(1)                    # set pin to on/high

p2 = Pin(Pin.cpu.P002, Pin.IN) # create input pin on P002
print(p2.value())              # get value, 0 or 1

p4 = Pin('P004', Pin.PULL_UP)      # enable internal pull-up register
p5 = Pin('P005', Pin.OUT, value=1) # set pin high on creation

Pin id is available corresponding to the RA MCU’s pin name which are Pin.cpu.P106 and ‘P106’. The RA MCU has many feature’s pins. However, there are some cases that pin feature is fixed or not connected by the board. Please confirm the board manual for the pin mapping.

UART (serial bus)

The RA MCU has some hardware UARTs called SCI (Serial Communication Interface). UART id is available corresponding to the RA MCU’s SCI number which are UART(0) as SCI0 and UART(1) as SCI1.

See machine.UART.

from machine import UART

uart1 = UART(1, 115200)
uart1.write('hello')    # write 5 bytes
uart1.read(5)           # read up to 5 bytes

Available UARTs and pins on the board are fixed and follows. One of these UARTs is used for REPL.

EK-RA4M1

UART0(REPL)

UART1

UART2

tx

P411

P401

P302

rx

P410

P402

P301

EK-RA4W1

UART1

UART4(REPL)

UART9

tx

P213

P204

P109

rx

P212

P206

P110

EK-RA6M1

UART0(REPL)

UART2

UART8

tx

P411

P302

P105

rx

P410

P301

P104

EK-RA6M2

UART0(REPL)

UART7

UART9

tx

P411

P401

P602

rx

P410

P402

P601

RA4M1-CLICKER

UART0

UART1(REPL)

tx

P411

P401

rx

P410

P402

Following functions are not supported at the present:

UART.init(baudrate)   # now only 115200 is confirmed
UART.init(cts, rts)   # Pins are fixed.
UART.init(invert)
UART.init(tx,rx)      # Pins are fixed.
UART.init(txbuf)
UART.init(flow)
UART.irq(handler)
UART.irq(trigger=RX_ANY)
UART.irq(priority)
UART.irq(wake=machine.IDLE)

Real time clock (RTC)

See machine.RTC

from machine import RTC

rtc = RTC()
rtc.datetime((2017, 8, 23, 1, 12, 48, 0, 0)) # set a specific date and time
                                             # time, eg 2017/8/23 1:12:48
rtc.datetime() # get date and time

Following functions are not supported at the present:

RTC.init(datetime)
RTC.now()
RTC.deinit()
RTC.alarm()
RTC.alarm_left()
RTC.cancel()
RTC.irq()

ADC (analog to digital conversion)

See machine.ADC

from machine import ADC

adc = ADC('P000')    # create an ADC object acting on a pin
adc.read_u16()       # read a raw analog value in the range 0-65535

Pin id is available corresponding to the RA MCU’s pin name which are ‘P000’ as AN000 (analog channel 000). The RA MCU has many analog channels. However, there are some cases that pin feature is fixed or not available by the board. Please confirm the MCU and board manual for the pin mapping.

Following functions are not supported at the present:

ADC.init()
ADC(sample_ns)
ADC(atten)
ADC.read_uv()
ADC.block()

SPI bus

The RA MCU has some hardware SPIs (Serial Peripheral Interface). SPI id is available corresponding to the RA MCU’s SPI number which are SPI(0) as SPI0 and SPI(1) as SPI1. If with no additional parameters, machine.SoftSPI() is called.

See machine.SPI.

from machine import SPI, Pin

spi = SPI(0, baudrate=500000)
cs = Pin.cpu.P103
cs(0)
spi.write(b"12345678")
cs(1)

Available SPIs and pins on the board are fixed and follows.

EK-RA4M1

SPI0

sck

P102

mosi

P101

miso

P100

cs

P206

EK-RA4W1

SPI0

sck

P102

mosi

P101

miso

P100

cs

P103

EK-RA6M1

SPI0

sck

P102

mosi

P101

miso

P100

cs

P103

EK-RA6M2

SPI0

SPI1

sck

P102

P702

mosi

P101

P701

miso

P100

P700

cs

P103

P703

RA4M1-CLICKER

SPI0

sck

P102

mosi

P101

miso

P100

cs

P103

Following functions are not supported at the present:

SPI.init(firstbit)    # now fixed with SPI.LSB
SPI.init(baudrate)    # now confirmed only 500000

I2C bus

The RA MCU has some hardware IIC (Inter-Integrated Circuit Bus). I2C id is available corresponding to the RA MCU’s I2C number which are I2C(0) as IIC0 and I2C(1) as IIC1. If with no additional parameters, machine.SoftI2C() is called.

See machine.I2C

from machine import I2C

i2c = I2C(0)

i2c.scan()         # returns list of slave addresses
i2c.readfrom_mem(0x50, 0x10, 2, addrsize=16)  # read 2 bytes from slave 0x50, slave memory 0x10

Available I2Cs and pins on the board are fixed and follows.

EK-RA4M1

scl

not supported

sda

not supported

EK-RA4W1

I2C0

scl

P204

sda

P407

EK-RA6M1

I2C0

scl

P400

sda

P401

EK-RA6M2

I2C2

scl

P512

sda

P511

RA4M1-CLICKER

I2C1

scl

P205

sda

P206

Following functions are not supported at the present:

I2C.init(freq)    # now confirmed only 400000
I2C.deinit()
I2C.start()
I2C.stop()

PWM (pulse width modulation)

PWM is not supported.

WDT (Watchdog timer)

WDT is not supported.

SDCard

The frozen sdcard driver (drivers/sdcard/sdcard.py) is available by connecting microSD card device to hardware SPI0 pins.:

from machine import Pin, SPI
import os, sdcard

spi = SPI(0, baudrate=500000)
cs = Pin.cpu.P103
sd = sdcard.SDCard(spi, cs)
os.mount(sd, '/sd')
os.listdir('/')
os.chdir('/sd')
os.umount('/sd')

OneWire driver

The OneWire driver is implemented in software and works on all pins:

from machine import Pin
import onewire

ow = onewire.OneWire(Pin(P012)) # create a OneWire bus on P012
ow.scan()               # return a list of devices on the bus
ow.reset()              # reset the bus
ow.readbyte()           # read a byte
ow.writebyte(0x12)      # write a byte on the bus
ow.write('123')         # write bytes on the bus
ow.select_rom(b'12345678') # select a specific device by its ROM code

There is a specific driver for DS18S20 and DS18B20 devices:

import time, ds18x20
ds = ds18x20.DS18X20(ow)
roms = ds.scan()
ds.convert_temp()
time.sleep_ms(750)
for rom in roms:
    print(ds.read_temp(rom))

Be sure to put a 4.7k pull-up resistor on the data line. Note that the convert_temp() method must be called each time you want to sample the temperature.

NeoPixel and APA106 driver

NeoPixel is not supported currently.