Intermediate
30 min

Master the art of precise timing with CS2200-CP and PIC32MZ2048EFH144

Clock frequency synthesizer

Clock Gen 4 Click with Fusion for PIC32 v8

Published May 27, 2023

Click board™

Clock Gen 4 Click

Dev Board

Fusion for PIC32 v8

Compiler

NECTO Studio

MCU

PIC32MZ2048EFH144

Integrate an advanced clock generator into your solution and witness the transformative impact on timing control

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Hardware Overview

How does it work?

Clock Gen 4 Click is based on the CS2200-CP, an analog PLL architecture comprised of a Delta-Sigma fractional-N frequency synthesizer from Cirrus Logic. The Delta-Sigma fractional-N frequency synthesizer has a high resolution for Input/Output clock ratios, low phase noise, a wide range of output frequencies, and the ability to tune to a new frequency quickly. This synthesizer multiplies the timing reference clock by the value of N to generate a stable and low-jitter PLL clock on the connector labeled PLL Clock. This Click board™ also has another connector marked as AUX Clock that outputs a buffered version of one of the input/output clocks or a status signal, depending on register configuration. The analog PLL-based frequency synthesizer uses a low-jitter timing reference clock

as a time and phase reference for the internal voltage-controlled oscillator (VCO). The phase comparator compares the fractional-N divided clock with the original timing reference and generates a control signal filtered by the internal loop filter to generate the VCO’s control voltage that sets its output frequency. The Delta-Sigma modulator modulates the loop integer divide ratio to get the desired fractional ratio between the reference clock and the VCO output. This allows fast lock times for various output frequencies without external filter components. Clock Gen 4 Click provides the possibility of using both I2C and SPI interfaces with a maximum frequency of 100kHz for I2C and 6MHz for SPI communication. The selection can be performed by positioning SMD jumpers labeled

COMM SEL to an appropriate position. Note that all the jumpers must be placed on the same side, or the Click board™ may become unresponsive. While the I2C interface is selected, the CS2200-CP allows the choice of the least significant bit (LSB) of its I2C slave address. This can be done by using the SMD jumper labeled as ADDR SEL. This Click board™ can only be operated with a 3.3V logic voltage level. The board must perform appropriate logic voltage level conversion before using MCUs with different logic levels. However, the Click board™ comes equipped with a library containing functions and an example code that can be used as a reference for further development.

clock-gen-4-click-hardware-overview

Features overview

Development board

Fusion for PIC32 v8 is a development board specially designed for the needs of rapid development of embedded applications. It supports a wide range of Microchip's PIC32 microcontrollers 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, Fusion for PIC32 v8 provides a fluid and immersive working experience, allowing access anywhere and under any circumstances at any time. Each part of the

Fusion for PIC32 v8 development board contains the components necessary for the most efficient operation of the same board. In addition to the advanced integrated CODEGRIP programmer/debugger module, which offers many valuable programming/debugging options and seamless integration with the Mikroe software environment, the board 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. Fusion for PIC32 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.

Fusion for PIC32 v8 horizontal image

Microcontroller Overview

MCU Card / MCU

default

Type

8th Generation

Architecture

PIC32

MCU Memory (KB)

2048

Silicon Vendor

Microchip

Pin count

144

RAM (Bytes)

524288

Used MCU Pins

mikroBUS™ mapper

NC
NC
AN
NC
NC
RST
SPI Chip Select
PH3
CS
SPI Clock
PD1
SCK
SPI Data OUT
PG8
MISO
SPI Data IN
PG7
MOSI
Power Supply
3.3V
3.3V
Ground
GND
GND
NC
NC
PWM
NC
NC
INT
NC
NC
TX
NC
NC
RX
I2C Clock
PA2
SCL
I2C Data
PA3
SDA
NC
NC
5V
Ground
GND
GND
1

Take a closer look

Schematic

Clock Gen 4 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 Fusion for PIC32 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 Clock Gen 4 Click driver.

Key functions:

  • void clockgen4_dev_ctl ( uint8_t dev_ctl ); - Function is used to write to Device Control register in order to apply settings.
  • void clockgen4_dev_cfg ( uint8_t dev_cfg ); - Function is used to write to Device Configuration 1 register in order to apply settings.
  • uint32_t clockgen4_set_ratio ( float ratio ); - Function is used to set the ratio between the output signal and the input clock.

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 ClockGen4 Click example
 *
 * # Description
 * This example demonstrates the use of Clock Gen 4 click which is based on CS2200-CP for changing the channel clock. The CS2200-CP is an extremely 
 * versatile system clocking device that utilizes a programmable phase lock loop. The CS2200-CP is based on an analog PLL architecture and this 
 * architecture allows for frequency synthesis and clock generation from a stable reference clock. The CS2200-CP supports both I²C and SPI for full software control.
 *
 * The demo application is composed of two sections :
 *
 * ## Application Init
 * Initializes I2C and SPI, sets CS pin as output and starts to write log, applies default settings and adjusted ratio to obtain a frequency.
 *
 * ## Application Task
 * Clock Gen 4 click is used in this example to generate and change the clock on the output channel.
 *
 * @author Jelena Milosavljevic
 *
 */

#include "board.h"
#include "log.h"
#include "clockgen4.h"

static clockgen4_t clockgen4;
static log_t logger;

uint8_t com_itfc = 0;

void application_init ( void ){
    log_cfg_t log_cfg;                     /**< Logger config object. */
    clockgen4_cfg_t clockgen4_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 " );
    
    Delay_ms( 100 );
    log_printf( &logger, "---------------------" );
    log_printf( &logger, "  Clock Gen 4 Click  " );
    log_printf( &logger, "---------------------" );
    
    // Click initialization.
    clockgen4_cfg_setup( &clockgen4_cfg );
    CLOCKGEN4_MAP_MIKROBUS( clockgen4_cfg, MIKROBUS_1 );
    err_t init_flag  = clockgen4_init( &clockgen4, &clockgen4_cfg );
    if ( ( I2C_MASTER_ERROR == init_flag ) || ( SPI_MASTER_ERROR == init_flag ) ) {
        log_error( &logger, " Application Init Error. " );
        log_info( &logger, " Please, run program again... " );

        for ( ; ; );
    }

    clockgen4_default_cfg ( &clockgen4 );
    log_info( &logger, " Application Task " );
    Delay_ms( 100 );
}

void application_task ( void ){
    clockgen4_dev_ctl ( &clockgen4, CLOCKGEN4_AUX_OUT_DIS | CLOCKGEN4_CLK_OUT_EN );
    log_printf( &logger, "  PLL Clock          \r\n" );
    log_printf( &logger, "  output enabled!    \r\n" );
    log_printf( &logger, "---------------------\r\n" );
    Delay_ms( 1000 );
    
    clockgen4_dev_ctl ( &clockgen4, CLOCKGEN4_AUX_OUT_EN | CLOCKGEN4_CLK_OUT_DIS );
    log_printf( &logger, "  AUX Clock          \r\n" );
    log_printf( &logger, "  output enabled!    \r\n" );
    log_printf( &logger, "---------------------\r\n" );
    Delay_ms( 1000 );
}

void main ( void ){
    application_init( );

    for ( ; ; ) {
        application_task( );
    }
}

// ------------------------------------------------------------------------ END

Additional Support

Resources