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Simplify data transfer between USB and UART devices with CP2110 and PIC18F86J50

From USB to UART in a blink!

USB UART 5 Click with UNI-DS v8

Published Nov 11, 2023

Click board™

USB UART 5 Click

Development board

UNI-DS v8

Compiler

NECTO Studio

MCU

PIC18F86J50

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.

USB UART 5 Click hardware overview image

Features overview

Development board

UNI-DS v8 is a development board specially designed for the needs of rapid development of embedded applications. It supports a wide range of microcontrollers, such as different STM32, Kinetis, TIVA, CEC, MSP, PIC, dsPIC, PIC32, and AVR MCUs regardless of their number of pins, and a broad set of unique functions, such as the first-ever embedded debugger/programmer over WiFi. The development board is well organized and designed so that the end-user has all the necessary elements, such as switches, buttons, indicators, connectors, and others, in one place. Thanks to innovative manufacturing technology, UNI-DS v8 provides a fluid and immersive working experience, allowing access anywhere and under any

circumstances at any time. Each part of the UNI-DS v8 development board contains the components necessary for the most efficient operation of the same board. An advanced integrated CODEGRIP programmer/debugger module offers many valuable programming/debugging options, including support for JTAG, SWD, and SWO Trace (Single Wire Output)), and seamless integration with the Mikroe software environment. Besides, it also includes a clean and regulated power supply module for the development board. It can use a wide range of external power sources, including a battery, an external 12V power supply, and a power source via the USB Type-C (USB-C) connector. Communication options such as USB-UART, USB

HOST/DEVICE, CAN (on the MCU card, if supported), and Ethernet is also included. In addition, it also has the well-established mikroBUS™ standard, a standardized socket for the MCU card (SiBRAIN standard), and two display options for the TFT board line of products and character-based LCD. UNI-DS v8 is an integral part of the Mikroe ecosystem for rapid development. Natively supported by Mikroe software tools, it covers many aspects of prototyping and development thanks to a considerable number of different Click boards™ (over a thousand boards), the number of which is growing every day.

UNI-DS v8 horizontal image

Microcontroller Overview

MCU Card / MCU

default

Type

8th Generation

Architecture

PIC

MCU Memory (KB)

64

Silicon Vendor

Microchip

Pin count

80

RAM (Bytes)

3904

Used MCU Pins

mikroBUS™ mapper

Suspend Mode
PA0
AN
Reset
PJ4
RST
UART RTS
PJ0
CS
NC
NC
SCK
NC
NC
MISO
NC
NC
MOSI
Power Supply
3.3V
3.3V
Ground
GND
GND
NC
NC
PWM
UART CTS
PB0
INT
UART TX
PG1
TX
UART RX
PG2
RX
NC
NC
SCL
NC
NC
SDA
NC
NC
5V
Ground
GND
GND
1

Take a closer look

Schematic

USB UART 5 Click Schematic schematic

Step by step

Project assembly

Fusion for PIC v8 front image hardware assembly

Start by selecting your development board and Click board™. Begin with the UNI-DS v8 as your development board.

Fusion for PIC v8 front image hardware assembly
GNSS2 Click front image hardware assembly
SiBRAIN for PIC32MZ1024EFK144 front image hardware assembly
GNSS2 Click complete accessories setup image hardware assembly
v8 SiBRAIN Access MB 1 - upright/background hardware assembly
Necto image step 2 hardware assembly
Necto image step 3 hardware assembly
Necto image step 4 hardware assembly
NECTO Compiler Selection Step Image hardware assembly
NECTO Output Selection Step Image hardware assembly
Necto image step 6 hardware assembly
Necto image step 7 hardware assembly
Necto image step 8 hardware assembly
Necto image step 9 hardware assembly
Necto image step 10 hardware assembly
Necto PreFlash Image hardware assembly

Track your results in real time

Application Output

After pressing the "FLASH" button on the left-side panel, it is necessary to open the UART terminal to display the achieved results. By clicking on the Tools icon in the right-hand panel, multiple different functions are displayed, among which is the UART Terminal. Click on the offered "UART Terminal" icon.

UART Application Output Step 1

Once the UART terminal is opened, the window takes on a new form. At the top of the tab are two buttons, one for adjusting the parameters of the UART terminal and the other for connecting the UART terminal. The tab's lower part is reserved for displaying the achieved results. Before connecting, the terminal has a Disconnected status, indicating that the terminal is not yet active. Before connecting, it is necessary to check the set parameters of the UART terminal. Click on the "OPTIONS" button.

UART Application Output Step 2

In the newly opened UART Terminal Options field, we check if the terminal settings are correct, such as the set port and the Baud rate of UART communication. If the data is not displayed properly, it is possible that the Baud rate value is not set correctly and needs to be adjusted to 115200. If all the parameters are set correctly, click on "CONFIGURE".

UART Application Output Step 3

The next step is to click on the "CONNECT" button, after which the terminal status changes from Disconnected to Connected in green, and the data is displayed in the Received data field.

UART Application Output Step 4

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

This example can be found in NECTO Studio. Feel free to download the code, or you can copy the code below.

/*!
 * @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

Additional Support

Resources