jumperless-boardboard-v5/RP23V50firmware/CodeDocs/Hardware_Interface_Guide.md

Hardware Interface Guide

This document provides an overview of the Jumperless hardware components that can be controlled and monitored through the MicroPython API.

Power System

Power Rails (TOP_RAIL, BOTTOM_RAIL)

The Jumperless board features two programmable power rails that run along the top and bottom of the breadboard.

• Voltage Range: -8.0V to +8.0V
• Control: Use the dac_set() function with the TOP_RAIL or BOTTOM_RAIL constants.
• Monitoring: The rail voltages can be monitored via the ADCs if connected.

Example:

# Set the top rail to 5V and the bottom rail to -5V
dac_set(TOP_RAIL, 5.0)
dac_set(BOTTOM_RAIL, -5.0)

Onboard Supplies (3V3, 5V)

The board provides fixed 3.3V and 5V power supplies.

• SUPPLY_3V3: A fixed 3.3V supply.
• SUPPLY_5V: A fixed 5V supply, typically from USB.
• These are available as nodes for connection but their voltage is not programmable.

Example:

# Connect a component to the 3.3V supply
connect(1, SUPPLY_3V3)

Analog I/O

DACs (Digital-to-Analog Converters)

Two general-purpose DACs are available for providing variable analog voltages.

• DAC0: 5V tolerant DAC output.
• DAC1: 8V tolerant DAC output.
• Control: Use dac_set(DAC0, voltage) or dac_set(DAC1, voltage).

Example:

# Generate a 1.25V signal on DAC1
dac_set(DAC1, 1.25)
connect(DAC1, 15) # Connect to breadboard row 15

ADCs (Analog-to-Digital Converters)

Multiple ADC channels are available for measuring analog voltages.

• Channels 0-3: 8V tolerant inputs.
• Channel 4: 5V tolerant input.
• Probe ADC (Channel 7): The ADC connected to the probe tip for measurements.
• Control: Use adc_get(channel) to read the voltage.

Example:

# Measure the voltage on ADC channel 2
voltage = adc_get(2)
print("Voltage at ADC2: " + str(voltage))

Digital I/O (GPIO)

The Jumperless provides 8 routable GPIO pins and 2 pins dedicated to UART.

• Pins: GPIO_1 through GPIO_8.
• Functions: Each pin can be configured as an input (with optional pull-up/pull-down resistors) or an output. They also support PWM.
• Control: Use the gpio_* and pwm_* functions.

Example:

# Blink an LED connected to GPIO_1
gpio_set_dir(GPIO_1, True) # Set as output
while True:
    gpio_set(GPIO_1, True)
    time.sleep(0.5)
    gpio_set(GPIO_1, False)
    time.sleep(0.5)

UART (Serial Communication)

Two pins are available for serial communication.

• UART_TX: Transmit pin.
• UART_RX: Receive pin.
• These can be used as standard GPIO pins or for serial communication with other devices.

Example:

# Connect the Jumperless UART to an external device
connect(UART_TX, "some_rx_pin")
connect(UART_RX, "some_tx_pin")

Current/Power Monitor (INA)

The INA219 sensors allow for monitoring current and power consumption.

• Sensor 0: General purpose current/power monitor.
• Sensor 1: Typically used for resistance measurement with DAC0.
• Control: Use the ina_* functions to get current, voltage, and power readings.

Example:

# Measure the current flowing through sensor 0
current = ina_get_current(0)
print("Current: " + str(current * 1000) + " mA")

Routable Buffer

A routable buffer is available for isolating or strengthening signals.

• BUFFER_IN: The input to the buffer.
• BUFFER_OUT: The output of the buffer.

Example:

# Pass a signal through the buffer
connect(some_signal_source, BUFFER_IN)
connect(BUFFER_OUT, some_destination)

Arduino Nano Interface

The Jumperless board has headers that are compatible with an Arduino Nano, and all of the Nano's pins are available as nodes in MicroPython.

• Digital Pins: D0 - D13
• Analog Pins: A0 - A7
• Power Pins: VIN, NANO_5V, NANO_3V3, NANO_GND_0, NANO_GND_1
• Other Pins: RESET, AREF

Example:

# Connect the Arduino's D13 pin to an LED on row 25
connect(D13, 25)
connect(NANO_GND_0, 26) # Provide ground for the LED