Intermediate
30 min

Captivate audiences and enhance your storytelling abilities with ISD3900 and ATmega1284

Your personalized digital voice recorder

Rec&Play Click with EasyAVR v7

Published Oct 22, 2023

Click board™

Rec&Play Click

Dev. board

EasyAVR v7

Compiler

NECTO Studio

MCU

ATmega1284

Discover how our multi-message record and playback device can bring your memories to life through customizable voice recordings

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Hardware Overview

How does it work?

Rec&Play Click is based on the ISD3900, a multi-message record and playback device with ChipCorder® technology, from Nuvoton. Thanks to the many useful features it offers, this IC gained its popularity very quickly. Besides several compression and de-compression CODEC, it features a fully programmable signal path with the support for several different signal types, allowing a very simple design for any kind of message-based application. Sound notification from a POS terminal, a home appliance that uses voice to notify about some event, even a Dictaphone-like device, it can all be implemented very quickly with this Click board™. Instead of using memory locations, ISD3900 allows using message indices: once stored, a message can be invoked using its index. Building of macro scripts (Voice Macros) is also possible. To allow the out-of-box functionality, the Click board™ is equipped with a small omnidirectional electret microphone, along with a miniature 8Ω speaker. The microphone is can capture a sound or voice recording. The recording can be reinforced by applying the Automatic Gain Control (AGC), which dynamically changes the input gain, helping to obtain the most appropriate signal level. The AGC function, along with many other functions, can be configured over the SPI interface. The miniature neodymium speaker (internal speaker) measures only 15 x 11mm, and it is designed to output up to 0.7W of continuous

power. It is driven by the ISD3900 IC, which integrates a small 0.5W class D amplifier. The internal speaker has an adhesive on its rims, allowing it to be easily mounted inside a small resonant box, which can reinforce its output. However, this speaker is good only when used indoors. 2-pole terminal labeled as EXT SPK allows an external passive speaker box to be connected. When the SPK SEL is moved to the EXT position, the output of the internal class D amplifier becomes routed to this connector, instead of the internal speaker. A differential BTL (Bridge-Tied Load) output is also available over the EXT SPK connector, allowing an external amplifier with differential inputs to be used. AUX IN and AUX OUT are 3.5mm jack connectors, used to connect line-level input and output signals. The AUX OUT connector offers a single-sided line-level output, compatible with most of the commercial amplifiers, active desktop speakers, sound monitors, etc. The AUX IN is a single-sided line-level input, allowing to capture sound from a home PC, TV set, MP3 player, and any other device equipped with the line-out connector. The audio sample rate is derived from an external crystal oscillator, rated at 4.096MHz. This crystal oscillator allows the master sample rate up to 32kHz. Lower sample rates can also be used, resulting in reduced sound quality. Besides the sample rate, the sound quality is also affected by the used

compression algorithm. ISD3900 supports many different CODECs. For more information, please refer to the ISD3900 IC datasheet. Besides the ISD3900 this Click board™ contains another IC: it is a non-volatile memory module labeled as W25Q64, a 64 Mbit serial Flash memory from Winbond. This memory module has a 64 Mbit density arranged in 8-bit words, allowing up to 32 minutes of audio to be stored. The ISD3900 has a set of registers that control every aspect of the device: the entire sound path can be configured by writing to the proper config registers over the SPI interface. The ISD3900 also handles Flash-related commands, such as formatting, erasing, reading, writing, and more. Although simplified, programming the ISD3900 can seem complex, but when used within the MIKROE environment, it is very easy to operate the Click board™. It is supported by the mikroSDK compatible library, which contains functions for accelerated software development. Several pre-configured sound path settings are available, saving valuable time. 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.

Rec&Play Click hardware overview image

Features overview

Development board

EasyAVR v7 is the seventh generation of AVR development boards specially designed for the needs of rapid development of embedded applications. It supports a wide range of 16-bit AVR microcontrollers from Microchip and has a broad set of unique functions, such as a powerful onboard mikroProg programmer and In-Circuit debugger over USB. The development board is well organized and designed so that the end-user has all the necessary elements in one place, such as switches, buttons, indicators, connectors, and others. With four different connectors for each port, EasyAVR v7 allows you to connect accessory boards, sensors, and custom electronics more

efficiently than ever. Each part of the EasyAVR v7 development board contains the components necessary for the most efficient operation of the same board. An integrated mikroProg, a fast USB 2.0 programmer with mikroICD hardware In-Circuit Debugger, offers many valuable programming/debugging options and seamless integration with the Mikroe software environment. Besides it also includes a clean and regulated power supply block for the development board. It can use a wide range of external power sources, including an external 12V power supply, 7-12V AC or 9-15V DC via DC connector/screw terminals, and a power source via the USB Type-B (USB-B)

connector. Communication options such as USB-UART and RS-232 are also included, alongside the well-established mikroBUS™ standard, three display options (7-segment, graphical, and character-based LCD), and several different DIP sockets which cover a wide range of 16-bit AVR MCUs. EasyAVR v7 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.

EasyAVR v7 horizontal image

Microcontroller Overview

MCU Card / MCU

ATmega1284

Architecture

AVR

MCU Memory (KB)

128

Silicon Vendor

Microchip

Pin count

40

RAM (Bytes)

16384

Used MCU Pins

mikroBUS™ mapper

SPI Ready Status
PA7
AN
Reset
PA6
RST
SPI Chip Select
PA5
CS
SPI Clock
PB7
SCK
SPI Data OUT
PB6
MISO
SPI Data IN
PB5
MOSI
Power Supply
3.3V
3.3V
Ground
GND
GND
NC
NC
PWM
Interrupt
PD2
INT
NC
NC
TX
NC
NC
RX
NC
NC
SCL
NC
NC
SDA
NC
NC
5V
Ground
GND
GND
1

Take a closer look

Click board™ Schematic

Rec&Play Click Schematic schematic

Step by step

Project assembly

EasyAVR v7 front image hardware assembly

Start by selecting your development board and Click board™. Begin with the EasyAVR v7 as your development board.

EasyAVR v7 front image hardware assembly
GNSS2 Click front image hardware assembly
GNSS2 Click complete accessories setup image hardware assembly
EasyAVR v7 Access DIP 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 DIP image step 7 hardware assembly
EasyPIC PRO v7a Display Selection Necto Step 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

1. Application Output - In Debug mode, the 'Application Output' window enables real-time data monitoring, offering direct insight into execution results. Ensure proper data display by configuring the environment correctly using the provided tutorial.

2. UART Terminal - Use the UART Terminal to monitor data transmission via a USB to UART converter, allowing direct communication between the Click board™ and your development system. Configure the baud rate and other serial settings according to your project's requirements to ensure proper functionality. For step-by-step setup instructions, refer to the provided tutorial.

3. Plot Output - The Plot feature offers a powerful way to visualize real-time sensor data, enabling trend analysis, debugging, and comparison of multiple data points. To set it up correctly, follow the provided tutorial, which includes a step-by-step example of using the Plot feature to display Click board™ readings. To use the Plot feature in your code, use the function: plot(*insert_graph_name*, variable_name);. This is a general format, and it is up to the user to replace 'insert_graph_name' with the actual graph name and 'variable_name' with the parameter to be displayed.

Software Support

Library Description

This library contains API for Rec&Play Click driver.

Key functions:

  • recplay_read_status - Function queries the ISD3900 device status

  • recplay_erase_msg - Function erases the message starting at the specified address

  • recplay_record_msg - Function initiates a managed record at first available location in memory

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 
 * \brief RecNPlay Click example
 * 
 * # Description
 * This application demonstrates the processof recording a message and playing it back.
 *
 * The demo application is composed of two sections :
 * 
 * ## Application Init 
 * Initializes SPI interface in proper mode and performs all the necessary commands to
 * put the device in proper working mode (chip reset, chip power up, chip erasing, clock configuration).
 * 
 * ## Application Task  
 * Performs the chip configuration for recording message via microphone, then records a message
 * for 8 seconds to specified memory location. After that, it reads the recorded message address with message length and then plays the
 * recorded message. When playback is done it erases the recorded message from memory. Afterwards, it repeats all the operations every 10 seconds.
 * 
 * *note:* 
 * The ISD3900 must be properly configured to work in record mode every time when user wants to record a message.
 * When user wants to play a recorded message, then ISD3900 must be properly configured, but now to work in play mode.
 * 
 * \author MikroE Team
 *
 */
// ------------------------------------------------------------------- INCLUDES

#include "board.h"
#include "log.h"
#include "recnplay.h"

// ------------------------------------------------------------------ VARIABLES

static recnplay_t recnplay;
static log_t logger;
static uint32_t msg_addr;
static uint16_t msg_len;
static uint8_t temp_var;
static uint8_t volume;
static RECNPLAY_RETVAL status_byte;
static uint8_t interr_byte;

static const uint8_t config_play_pwm_spk[ 32 ] = { 0x64, 0x00, 0x44, 0x00, 0x40, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x26, 0x00, 0x57, 0x01, 0x57, 0x00, 0x00, 0xFF, 0x30, 0x02, 0x00, 0x00, 0x00, 0xFF, 0x00, 0xFF, 0x00, 0x00 };
static const uint8_t config_play_aux_out[ 32 ] = { 0x64, 0x00, 0x48, 0x00, 0x40, 0x80, 0xC1, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x26, 0x00, 0x57, 0x01, 0x57, 0x00, 0x00, 0xFF, 0x30, 0x02, 0xAB, 0x00, 0x00, 0xFF, 0x00, 0xFF, 0x00, 0x00 };
static const uint8_t config_rec_mic[ 32 ]      = { 0xA4, 0x80, 0x02, 0xFF, 0x0D, 0x40, 0x50, 0x48, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x28, 0x00, 0x3E, 0x00, 0xD6, 0x00, 0xFF, 0xFF, 0x11, 0x82, 0x00, 0x00, 0x00, 0xFF, 0x00, 0xFF, 0x00, 0x00 };


// ------------------------------------------------------- ADDITIONAL FUNCTIONS

void wait_cmd_fin ( void )
{
    status_byte = recplay_read_status( &recnplay, &interr_byte );
    while ( ( interr_byte != RECPLAY_INT_CMD_FIN_MASK ) || 
                ( status_byte != ( RECPLAY_STAT_DBUF_RDY_MASK | RECPLAY_STAT_INT_GEN_MASK ) ) )
    {
        status_byte = recplay_read_status( &recnplay, &interr_byte );
    }
    status_byte = recplay_read_interr( &recnplay, &interr_byte );
}

void wait_ready ( void )
{
    status_byte = recplay_read_status( &recnplay, &interr_byte );
    while ( status_byte != RECPLAY_STAT_DBUF_RDY_MASK )
    {
        status_byte = recplay_read_status( &recnplay, &interr_byte );
    }
    status_byte = recplay_read_interr( &recnplay, &interr_byte );
}

void wait_power_up ( void )
{
    status_byte = recplay_read_status( &recnplay, &interr_byte );
    while ( status_byte == RECPLAY_STAT_PWR_DOWN_MASK )
    {
        status_byte = recplay_read_status( &recnplay, &interr_byte );
    }
    status_byte = recplay_read_interr( &recnplay, &interr_byte );
}

void time_record ( uint32_t seconds_time )
{
    uint8_t cnt;
    for ( cnt = 0; cnt < seconds_time; cnt++ )
    {
        Delay_ms ( 1000 );
        log_printf( &logger, "." );
    }
}

void set_volume ( uint8_t volume_sel )
{
    uint16_t volume_res;

    if ( volume_sel > 100 )
    {
        volume = 0;
        log_printf( &logger, "Volume is: 100%\r\n" );
        return;
    }

    volume_res = 255 * volume_sel;
    volume_res /= 100;
    volume = 255 - volume_res;

    log_printf( &logger, "Volume is: %u%%\r\n", ( uint16_t ) volume_sel );
}

// ------------------------------------------------------ APPLICATION FUNCTIONS

void application_init ( void )
{
    log_cfg_t log_cfg;
    recnplay_cfg_t cfg;

    /** 
     * 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.

    recnplay_cfg_setup( &cfg );
    RECNPLAY_MAP_MIKROBUS( cfg, MIKROBUS_1 );
    recnplay_init( &recnplay, &cfg );

    log_printf( &logger, "Chip reset...\r\n" );
    recplay_reset( &recnplay );
    log_printf( &logger, "Power up...\r\n" );
    recplay_pwr_up( &recnplay );
    wait_power_up( );
    log_printf( &logger, "Chip Erasing...\r\n" );
    recplay_erase_chip( &recnplay );
    wait_cmd_fin( );
    log_printf( &logger, "Clock Configuration...\r\n" );
    status_byte = recplay_set_clk_cnfg( &recnplay, 0x34 );
    log_printf( &logger, "----------------------------\r\n" );
    volume = 0;
    Delay_ms ( 1000 );
}

void application_task ( void )
{
    uint8_t cnt;
    log_printf( &logger, "Preparing to record a message\r\n" );
    for ( cnt = 0; cnt < 32; cnt++ )
    {
        if ( ( cnt != RECPLAY_CFG0A_REG ) && ( cnt != RECPLAY_CFG1C_REG ) && ( cnt != RECPLAY_CFG1E_REG ) )
        {
            wait_ready( );
            temp_var = config_rec_mic[ cnt ];
            status_byte = recplay_write_cnfg_reg( &recnplay, cnt, &temp_var, 1 );
        }
    }
    wait_ready( );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );

    log_printf( &logger, "Message recording" );
    status_byte = recplay_record_msg_addr( &recnplay, 0x12000 );
    time_record( 8 );
    status_byte = recplay_stop( &recnplay );
    wait_cmd_fin( );
    log_printf( &logger, "End of recording\r\n" );

    status_byte = recplay_read_msg_addr( &recnplay, &msg_addr, &msg_len );
    log_printf( &logger, "Message Address: 0x%lx\r\n", msg_addr );
    log_printf( &logger, "Message Length: %u\r\n", msg_len );
    Delay_ms ( 1000 );

    log_printf( &logger, "Preparing to play a message\r\n" );
    set_volume( 100 );
    for ( cnt = 0; cnt < 32; cnt++ )
    {
        if ( ( cnt != RECPLAY_CFG0A_REG ) && ( cnt != RECPLAY_CFG1C_REG ) && ( cnt != RECPLAY_CFG1E_REG ) )
        {
            wait_ready( );

            if ( cnt == RECPLAY_CFG03_REG )
            {
                temp_var = volume;
            }
            else
            {
                temp_var = config_play_pwm_spk[ cnt ];
            }
            status_byte = recplay_write_cnfg_reg( &recnplay, cnt, &temp_var, 1 );
        }
    }

    wait_ready( );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );

    log_printf( &logger, "Message is playing...\r\n" );
    status_byte = recplay_play_msg( &recnplay, 0x12000, 0 );
    wait_cmd_fin( );
    log_printf( &logger, "End of playing...\r\n" );


    log_printf( &logger, "Status Byte: 0x%x\r\n", ( uint16_t ) status_byte );
    log_printf( &logger, "Interrupt byte: 0x%x\r\n", ( uint16_t ) interr_byte );
    Delay_ms ( 1000 );

    log_printf( &logger, "Message erasing...\r\n" );
    status_byte = recplay_erase_msg( &recnplay, 0x12000 );
    wait_cmd_fin( );
    log_printf( &logger, "End of erasing\r\n" );

    log_printf( &logger, "----------------------------\r\n" );
    Delay_ms ( 1000 );
}

int main ( void ) 
{
    /* Do not remove this line or clock might not be set correctly. */
    #ifdef PREINIT_SUPPORTED
    preinit();
    #endif
    
    application_init( );
    
    for ( ; ; ) 
    {
        application_task( );
    }

    return 0;
}

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

Additional Support

Resources

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