Simplify data transfer between USB and UART devices with CP2110 and ATmega328P
From USB to UART in a blink!
Published Feb 14, 2024
Click board™
USB UART 5 Click
Dev Board
Arduino UNO Rev3
Compiler
NECTO Studio
MCU
ATmega328P
Revolutionize your data communication projects with the USB to UART magic – a compact and efficient solution that connects your devices swiftly and flawlessly.
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Hardware Overview
How does it work?
USB UART 5 Click is based on the CP2110, a single-chip HID USB to UART bridge controller from Silicon Labs. A USB function controller in the CP2110 is a USB 2.0-compliant, full-speed device with an integrated USB transceiver, one-time programmable ROM, and an asynchronous serial data bus (UART) in one compact package. The UART capabilities of the CP2110 include baud rate support from 300 to 1Mbps, hardware flow control, RS-485 support, and GPIO signals that are user-defined for status and control information. The USB function controller manages all data transfers between USB and UART, command requests generated by the USB host controller, and commands for controlling the function of the UARTs and GPIO pins. The CP2110 uses the standard USB HID device class, natively supported by most operating systems. A custom driver does
not need to be installed for this device. In addition, the CP2110 also supports USB Suspend and Resume modes for power management purposes. The CP2110 enters Suspend mode when Suspend signaling is detected on the bus using the SPD pin of the mikroBUS™ socket. Upon entering Suspend mode, the SPD signal is asserted, but it can also be asserted after a reset condition (RST pin) until device configuration during USB Enumeration is complete. SPD pin detects logic high level when the device is in the Suspend state and logic low when the device is in Normal mode, which is also visually indicated via red LED labeled as CONNECTED. This Click board™ also features 8 GPIO signals, located on unpopulated headers, that are user-defined for status and control information. Four GPIO signals support alternate features, including a configurable clock output
(CLK) from 24MHz to 47kHz, RS-485 transceiver control, and TX and RX LED toggle features. Also, the USB UART 5 Click can work in a USB-powered configuration thanks to the ability of the CP2110 to provide adequate power to all its parts with the help of an internal regulator using the USB bus voltage. To select this mode of operation, it is necessary to switch the jumper PWR SEL to the position marked with VBUS. This Click board™ can be operated only with a 3.3V logic voltage level. The board must perform appropriate logic voltage level conversion before using MCUs with different logic levels. Also, it comes equipped with a library containing functions and an example code that can be used as a reference for further development.
Features overview
Development board
Arduino UNO is a versatile microcontroller board built around the ATmega328P chip. It offers extensive connectivity options for various projects, featuring 14 digital input/output pins, six of which are PWM-capable, along with six analog inputs. Its core components include a 16MHz ceramic resonator, a USB connection, a power jack, an
ICSP header, and a reset button, providing everything necessary to power and program the board. The Uno is ready to go, whether connected to a computer via USB or powered by an AC-to-DC adapter or battery. As the first USB Arduino board, it serves as the benchmark for the Arduino platform, with "Uno" symbolizing its status as the
first in a series. This name choice, meaning "one" in Italian, commemorates the launch of Arduino Software (IDE) 1.0. Initially introduced alongside version 1.0 of the Arduino Software (IDE), the Uno has since become the foundational model for subsequent Arduino releases, embodying the platform's evolution.
Microcontroller Overview
MCU Card / MCU
Architecture
AVR
MCU Memory (KB)
32
Silicon Vendor
Microchip
Pin count
28
RAM (Bytes)
2048
You complete me!
Accessories
Click Shield for Arduino UNO has two proprietary mikroBUS™ sockets, allowing all the Click board™ devices to be interfaced with the Arduino UNO board without effort. The Arduino Uno, a microcontroller board based on the ATmega328P, provides an affordable and flexible way for users to try out new concepts and build prototypes with the ATmega328P microcontroller from various combinations of performance, power consumption, and features. The Arduino Uno has 14 digital input/output pins (of which six can be used as PWM outputs), six analog inputs, a 16 MHz ceramic resonator (CSTCE16M0V53-R0), a USB connection, a power jack, an ICSP header, and reset button. Most of the ATmega328P microcontroller pins are brought to the IO pins on the left and right edge of the board, which are then connected to two existing mikroBUS™ sockets. This Click Shield also has several switches that perform functions such as selecting the logic levels of analog signals on mikroBUS™ sockets and selecting logic voltage levels of the mikroBUS™ sockets themselves. Besides, the user is offered the possibility of using any Click board™ with the help of existing bidirectional level-shifting voltage translators, regardless of whether the Click board™ operates at a 3.3V or 5V logic voltage level. Once you connect the Arduino UNO board with our Click Shield for Arduino UNO, you can access hundreds of Click boards™, working with 3.3V or 5V logic voltage levels.
Used MCU Pins
mikroBUS™ mapper
Take a closer look
Click board™ Schematic
Step by step
Project assembly
Start by selecting your development board and Click board™. Begin with the Arduino UNO Rev3 as your development board.
Track your results in real time
Application Output
This Click board can be interfaced and monitored in two ways:
Application Output- Use the "Application Output" window in Debug mode for real-time data monitoring. Set it up properly by following this tutorial.
UART Terminal- Monitor data via the UART Terminal using a USB to UART converter. For detailed instructions, check out this tutorial.
Software Support
Library Description
This library contains API for USB UART 5 Click driver.
Key functions:
usbuart5_generic_write- USB UART 5 data writing function.usbuart5_generic_read- USB UART 5 data reading function.usbuart5_reset_device- USB UART 5 reset the device function.
Open Source
Code example
The complete application code and a ready-to-use project are available through the NECTO Studio Package Manager for direct installation in the NECTO Studio. The application code can also be found on the MIKROE GitHub account.
/*!
* @file main.c
* @brief USB UART 5 Click Example.
*
* # Description
* This example reads and processes data from USB UART 5 Click board™.
* The library initializes and defines the UART bus drivers
* to transmit or receive data.
*
* The demo application is composed of two sections :
*
* ## Application Init
* Initializes driver, wake-up module, and performs the default configuration.
*
* ## Application Task
* Any data which the host PC sends via HidUartExample
* will be sent over USB to the click board and then it will be read and
* echoed back by the MCU to the PC where the terminal program will display it.
* Results are being sent to the UART Terminal, where you can track their changes.
*
* @note
* Make sure to download and install
* CP2110/4 Software package for Windows/Mac/Linux on the host PC.
*
* @author Nenad Filipovic
*
*/
#include "board.h"
#include "log.h"
#include "usbuart5.h"
static usbuart5_t usbuart5;
static log_t logger;
void application_init ( void )
{
log_cfg_t log_cfg; /**< Logger config object. */
usbuart5_cfg_t usbuart5_cfg; /**< Click config object. */
/**
* Logger initialization.
* Default baud rate: 115200
* Default log level: LOG_LEVEL_DEBUG
* @note If USB_UART_RX and USB_UART_TX
* are defined as HAL_PIN_NC, you will
* need to define them manually for log to work.
* See @b LOG_MAP_USB_UART macro definition for detailed explanation.
*/
LOG_MAP_USB_UART( log_cfg );
log_init( &logger, &log_cfg );
log_info( &logger, " Application Init " );
// Click initialization.
usbuart5_cfg_setup( &usbuart5_cfg );
USBUART5_MAP_MIKROBUS( usbuart5_cfg, MIKROBUS_1 );
if ( UART_ERROR == usbuart5_init( &usbuart5, &usbuart5_cfg ) )
{
log_error( &logger, " Communication init." );
for ( ; ; );
}
usbuart5_default_cfg ( &usbuart5 );
log_info( &logger, " Application Task " );
}
void application_task ( void )
{
char rx_data = 0;
if ( usbuart5_generic_read ( &usbuart5, &rx_data, 1 ) )
{
if ( usbuart5_generic_write ( &usbuart5, &rx_data, 1 ) )
{
log_printf( &logger, "%c", rx_data );
}
}
}
void main ( void )
{
application_init( );
for ( ; ; )
{
application_task( );
}
}
// ------------------------------------------------------------------------ END
