Transform your projects with interface precision, as our bridge technology allows you to bridge the gap between I2C and SPI, optimizing data exchange, reducing complexity, and enhancing compatibility within your electronic applications
A
A
Hardware Overview
How does it work?
I2C to SPI Click is based on two SC18IS602B, an I2C-bus to SPI bridge from NXP Semiconductor. This IC bridges the data communication between the two interfaces, offering many additional features, such as the programmable I/O, internal oscillator option, active low interrupt output, low power mode, and more. The SC18IS602B operates as an I2C-bus slave-transmitter or slave-receiver and an SPI master. The SC18IS602B controls all the SPI bus-specific sequences, protocol, and timing. It also has its own internal oscillator, and it supports SPI chip select output that may be configured as GPIO when not used. This allows the software to be easily written or ported from another platform. The I2C to SPI Click provides a byte-oriented I2C-bus interface that supports data transfers up to 400 kHz. When the I2C-bus master is reading data from the click board™, the device will be a slave-transmitter. It also can be a slave-receiver when the I2C-bus master is sending data. The SC18IS602B acts as an I2C-bus master at no time. However, it does have the ability to hold the SCL
line LOW between bytes to complete its internal processes. A slave address of the SC18IS602B is comprised of a fixed and a programmable part. The programmable part of the slave address enables the maximum possible number of such devices to be connected to the I2C-bus. Since the SC18IS602B has three programmable address bits (defined by the A2, A1, and A0 pins), it is possible to have eight of these devices on the same bus. Therefore, this Click board™ is equipped with three SMD jumpers, grouped under the ADDR SEL label, used to select the I2C slave address. By moving the jumpers at the desired position, the user can select the address used for the communication with the host MCU. The #RESET pin performs the hardware reset of the SC18IS602B IC. The #RESET pin is routed to the mikroBUS™ RST pin and it is active LOW. The #INT allows the host MCU to receive an interrupt from the SC18IS602B IC. An interrupt is generated by the SC18IS602B after any SPI transmission has been completed. Therefore, the #INT of the
SC18IS602B is routed to the INT pin of the mikroBUS™ socket. The interrupt can be cleared (INT pin HIGH) by sending a ‘Clear Interrupt’ command, although It is not necessary. This allows more optimized software (firmware) to be written, as the host MCU does not have to continuously poll the LSR register to see if any interrupt needs to be serviced. The datasheet of the SC18IS602B offers more information about using and configuring the SC18IS602B IC. However, the Click board™ is supported by a mikroSDK library, offering functions that simplify the prototyping and firmware development. 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
PIC18F57Q43 Curiosity Nano evaluation kit is a cutting-edge hardware platform designed to evaluate microcontrollers within the PIC18-Q43 family. Central to its design is the inclusion of the powerful PIC18F57Q43 microcontroller (MCU), offering advanced functionalities and robust performance. Key features of this evaluation kit include a yellow user LED and a responsive
mechanical user switch, providing seamless interaction and testing. The provision for a 32.768kHz crystal footprint ensures precision timing capabilities. With an onboard debugger boasting a green power and status LED, programming and debugging become intuitive and efficient. Further enhancing its utility is the Virtual serial port (CDC) and a debug GPIO channel (DGI
GPIO), offering extensive connectivity options. Powered via USB, this kit boasts an adjustable target voltage feature facilitated by the MIC5353 LDO regulator, ensuring stable operation with an output voltage ranging from 1.8V to 5.1V, with a maximum output current of 500mA, subject to ambient temperature and voltage constraints.
Microcontroller Overview
MCU Card / MCU
Architecture
PIC
MCU Memory (KB)
128
Silicon Vendor
Microchip
Pin count
48
RAM (Bytes)
8196
You complete me!
Accessories
Curiosity Nano Base for Click boards is a versatile hardware extension platform created to streamline the integration between Curiosity Nano kits and extension boards, tailored explicitly for the mikroBUS™-standardized Click boards and Xplained Pro extension boards. This innovative base board (shield) offers seamless connectivity and expansion possibilities, simplifying experimentation and development. Key features include USB power compatibility from the Curiosity Nano kit, alongside an alternative external power input option for enhanced flexibility. The onboard Li-Ion/LiPo charger and management circuit ensure smooth operation for battery-powered applications, simplifying usage and management. Moreover, the base incorporates a fixed 3.3V PSU dedicated to target and mikroBUS™ power rails, alongside a fixed 5.0V boost converter catering to 5V power rails of mikroBUS™ sockets, providing stable power delivery for various connected devices.
Used MCU Pins
mikroBUS™ mapper
Take a closer look
Schematic
Step by step
Project assembly
Track your results in real time
Application Output via Debug Mode
1. Once the code example is loaded, pressing the "DEBUG" button initiates the build process, programs it on the created setup, and enters Debug mode.
2. After the programming is completed, a header with buttons for various actions within the IDE becomes visible. Clicking the green "PLAY" button starts reading the results achieved with the Click board™. The achieved results are displayed in the Application Output tab.
Software Support
Library Description
This library contains API for I2C to SPI Click driver.
Key functions:
i2ctospi_spi_write_byte
- Function SPI write the byte of data to the targeted 8-bit register address of the SC18IS602B I2C-bus to SPI bridge on the I2C to SPI Clicki2ctospi_spi_read_byte
- Function SPI read the byte of data from the targeted 8-bit register address of the SC18IS602B I2C-bus to SPI bridge on the I2C to SPI Clicki2ctospi_clear_interrupt
- Function clear interrupt is generated by the SC18IS602B after any SPI transmission has been completed
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
* \brief I2cToSpi Click example
*
* # Description
* I2C to SPi Click allows serving as an interface between a standard I2C-bus of a microcontroller
* and an SPi bus, which allows the microcontroller to communicate directly with SPi devices
* through its I2C-bus. By offering an I2C-bus slave-transmitter or slave-receiver and SPI master,
* this Click controls all the SPi bus-specific sequences, protocol, and timing. It also has its own
* internal oscillator, and it supports the SPi chip select output that may be configured as GPIO when not used.
*
* The demo application is composed of two sections :
*
* ## Application Init
* Initialization driver enable's - I2C,
* hardware reset, SS0 ( CS ) configured to be used as slave select outputs, set the configuration of SPI:
* order MSB first, clock Idle low, leading-edge transition, SPI clock rate to 115kHz,
* set SPI EEPROM write enable SS0, clear interrupt,
* clear RT5 register, sets starting time: hours, minutes and seconds ( enable counting ), also write log.
*
* ## Application Task
* This is an example which demonstrates the use of RTC 5 click is wired to I2C to SPI click board.
* I2C to SPI click communicates with register via the I2C interface,
* serve as an interface between a standard I2C-bus of a microcontroller and an SPI bus.
* RTC 5 click communicates with register via SPI interface.
* In this examples, we display RTC time which we received reading from the target register
* address of MCP79510 chip on RTC 5 click board via I2C interface of I2C to SPI click board.
* Results are being sent to the Usart Terminal where you can track their changes.
* All data logs write on usb uart changes for every 1 sec.
*
* *note:*
* <pre>
* Additional Functions :
* - void display_log_uart( uint8_t value ) - Write the value of time or date as a two-digit number.
* - void rtc5_clear( i2ctospi_t *ctx, i2ctospi_spi_t *spi ) - Clear RTCC and SRAM memory of RTC 5 click.
* - void rtc5_set_time_seconds( i2ctospi_t *ctx, i2ctospi_spi_t *spi, uint8_t seconds ) - Set the seconds and enable counting.
* - uint8_t rtc5_get_time_seconds( i2ctospi_t *ctx, i2ctospi_spi_t *spi ) - Get the seconds.
* - void rtc5_set_time_minutes( uint8_t minutes ) - Set the minutes.
* - uint8_t rtc5_get_time_minutes( i2ctospi_t *ctx, i2ctospi_spi_t *spi ) - Get the minutes.
* - void rtc5_set_time_hours( i2ctospi_t *ctx, i2ctospi_spi_t *spi, uint8_t hours ) - Set the hours.
* - uint8_t rtc5_get_time_hours( i2ctospi_t *ctx, i2ctospi_spi_t *spi ) - Get the hours.
* </pre>
*
* \author MikroE Team
*
*/
// ------------------------------------------------------------------- INCLUDES
#include "board.h"
#include "log.h"
#include "i2ctospi.h"
// ------------------------------------------------------------------ VARIABLES
static i2ctospi_t i2ctospi;
static i2ctospi_spi_t i2ctospi_spi;
static i2ctospi_gpio_t i2ctospi_gpio;
static log_t logger;
static uint8_t time_hours;
static uint8_t time_minutes;
static uint8_t time_seconds;
static uint8_t time_seconds_new = 0xFF;
// ------------------------------------------------------- ADDITIONAL FUNCTIONS
void display_log_uart ( uint8_t value )
{
log_printf( &logger, " %d%d ", ( uint16_t )( value / 10 ), ( uint16_t )( value % 10 ) );
}
void rtc5_clear ( i2ctospi_t *ctx, i2ctospi_spi_t *spi )
{
uint8_t reg_add;
spi->slave_device = I2CTOSPI_SLAVEDEVICE_SS0;
spi->function_id = I2CTOSPI_RTC5_COMMAND_WRITE;
spi->reg_addr = reg_add;
for ( reg_add = 0; reg_add < 0x20; reg_add++ )
{
i2ctospi_spi_write_byte( ctx, spi, 0x00 );
Delay_1us( );
}
spi->reg_addr = I2CTOSPI_RTC5_COMMAND_CLEAR;
i2ctospi_spi_write_byte( ctx, spi, 0x00 );
i2ctospi_clear_interrupt( ctx );
}
void rtc5_set_time_seconds ( i2ctospi_t *ctx, i2ctospi_spi_t *spi, uint8_t seconds )
{
uint8_t ones;
uint8_t tens;
uint8_t temp;
ones = 0x00;
tens = 0x00;
seconds %= 60;
ones = seconds % 10;
tens = ( seconds / 10 ) << 4;
temp = tens | ones;
temp |= I2CTOSPI_RTC5_COMMAND_ENABLE_COUNTING;
spi->slave_device = I2CTOSPI_SLAVEDEVICE_SS0;
spi->function_id = I2CTOSPI_RTC5_COMMAND_WRITE;
spi->reg_addr = I2CTOSPI_RTC5_REG_TIME_SEC;
i2ctospi_spi_write_byte( ctx, spi, temp );
}
uint8_t rtc5_get_time_seconds ( i2ctospi_t *ctx, i2ctospi_spi_t *spi )
{
uint8_t ones;
uint8_t tens;
uint8_t result_sec;
uint8_t temp;
spi->slave_device = I2CTOSPI_SLAVEDEVICE_SS0;
spi->function_id = I2CTOSPI_RTC5_COMMAND_READ;
spi->reg_addr = I2CTOSPI_RTC5_REG_TIME_SEC;
temp = i2ctospi_spi_read_byte( ctx, spi );
ones = temp & 0x0F;
tens = ( temp & 0x70 ) >> 4;
result_sec = ( 10 * tens ) + ones;
return result_sec;
}
void rtc5_set_time_minutes ( i2ctospi_t *ctx, i2ctospi_spi_t *spi, uint8_t minutes )
{
uint8_t ones;
uint8_t tens;
uint8_t temp;
ones = 0x00;
tens = 0x00;
minutes %= 60;
ones = minutes % 10;
tens = ( minutes / 10 ) << 4;
temp = tens | ones;
spi->slave_device = I2CTOSPI_SLAVEDEVICE_SS0;
spi->function_id = I2CTOSPI_RTC5_COMMAND_WRITE;
spi->reg_addr = I2CTOSPI_RTC5_REG_TIME_MIN;
i2ctospi_spi_write_byte( ctx, spi, temp );
}
uint8_t rtc5_get_time_minutes ( i2ctospi_t *ctx, i2ctospi_spi_t *spi )
{
uint8_t ones;
uint8_t tens;
uint8_t result_min;
uint8_t temp;
spi->slave_device = I2CTOSPI_SLAVEDEVICE_SS0;
spi->function_id = I2CTOSPI_RTC5_COMMAND_READ;
spi->reg_addr = I2CTOSPI_RTC5_REG_TIME_MIN;
temp = i2ctospi_spi_read_byte( ctx, spi );
ones = temp & 0x0F;
tens = ( temp & 0x70 ) >> 4;
result_min = ( 10 * tens ) + ones;
return result_min;
}
void rtc5_set_time_hours ( i2ctospi_t *ctx, i2ctospi_spi_t *spi, uint8_t hours )
{
uint8_t ones;
uint8_t tens;
uint8_t temp;
ones = 0x00;
tens = 0x00;
hours %= 24;
ones = hours % 10;
tens = ( hours / 10 ) << 4;
temp = tens | ones;
spi->slave_device = I2CTOSPI_SLAVEDEVICE_SS0;
spi->function_id = I2CTOSPI_RTC5_COMMAND_WRITE;
spi->reg_addr = I2CTOSPI_RTC5_REG_TIME_HOUR,
i2ctospi_spi_write_byte( ctx, spi, temp );
}
uint8_t rtc5_get_time_hours ( i2ctospi_t *ctx, i2ctospi_spi_t *spi )
{
uint8_t ones;
uint8_t tens;
uint8_t result_hours;
uint8_t temp;
spi->slave_device = I2CTOSPI_SLAVEDEVICE_SS0;
spi->function_id = I2CTOSPI_RTC5_COMMAND_READ;
spi->reg_addr = I2CTOSPI_RTC5_REG_TIME_HOUR;
temp = i2ctospi_spi_read_byte( ctx, spi );
ones = temp & 0x0F;
tens = ( temp & 0x30 ) >> 4;
result_hours = ( 10 * tens ) + ones;
return result_hours;
}
// ------------------------------------------------------ APPLICATION FUNCTIONS
void application_init ( void )
{
log_cfg_t log_cfg;
i2ctospi_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.
i2ctospi_cfg_setup( &cfg );
I2CTOSPI_MAP_MIKROBUS( cfg, MIKROBUS_1 );
i2ctospi_init( &i2ctospi, &cfg );
i2ctospi_default_cfg( &i2ctospi );
//Set Time : 23h 59m 48s
rtc5_clear( &i2ctospi, &i2ctospi_spi );
rtc5_set_time_hours( &i2ctospi, &i2ctospi_spi, 23 );
Delay_1ms( );
rtc5_set_time_minutes( &i2ctospi, &i2ctospi_spi, 59 );
Delay_1ms( );
rtc5_set_time_seconds( &i2ctospi, &i2ctospi_spi, 48 );
Delay_1ms( );
}
void application_task ( void )
{
time_seconds = rtc5_get_time_seconds( &i2ctospi, &i2ctospi_spi );
Delay_1ms( );
time_minutes = rtc5_get_time_minutes( &i2ctospi, &i2ctospi_spi );
Delay_1ms( );
time_hours = rtc5_get_time_hours( &i2ctospi, &i2ctospi_spi );
Delay_1ms( );
if ( time_seconds_new != time_seconds )
{
log_printf( &logger, " Time : " );
display_log_uart( time_hours );
log_printf( &logger, ":" );
display_log_uart( time_minutes );
log_printf( &logger, ":" );
display_log_uart( time_seconds );
log_printf( &logger, "\r\n" );
log_printf( &logger, "------------------\r\n" );
time_seconds_new = time_seconds;
}
Delay_1ms( );
}
void main ( void )
{
application_init( );
for ( ; ; )
{
application_task( );
}
}
// ------------------------------------------------------------------------ END