Led Ring R Click

How does it work?

LED Ring R Click is based on four SN74HC595, an 8-bit serial-in, parallel-out 3-state shift register output latches from Texas Instruments. The SN74HC595s are connected in a daisy chain from one’s serial data output pin to another serial data input pin. Both the shift and storage registers have separate clocks. The data in the shift register is transferred to the storage register on a LOW-to-HIGH transition of the LAT pin. If both clocks are logic state timed together, the shift register will always be one clock pulse ahead of the storage register. Data in the storage register appears at the output whenever the output enable pin (OE) is LOW (in this case, always since the OE pin is connected to GND and is always low).

The LED Ring R Click uses an SPI serial interface to communicate with the host MCU via the mikroBUS™ socket. The CLK pin serves as a shift register clock input, while the LAT pin serves as a storage register clock input for all four SN74HC595. The MR pin is a master reset pin with active LOW and will reset all four SN74HC595 shift registers at once. All four SN74HC595 outputs are enabled by default, as they are pulled down, and the enabling feature on this Click board™ is not given to the user.

This Click board™ can operate with either 3.3V or 5V logic voltage levels selected via the 3.3V 5V jumper. This way, both 3.3V and 5V capable MCUs can use the communication lines properly. However, the Click board™ comes equipped with a library containing easy-to-use functions and an example code that can be used, as a reference, for further development.

Specifications

Pinout diagram

This table shows how the pinout on Led ring R Click corresponds to the pinout on the mikroBUS™ socket (the latter shown in the two middle columns).

Notes	Pin					Pin	Notes
	NC	1	AN	PWM	16	NC
Master Reset	MR	2	RST	INT	15	NC
Latch Signal	LAT	3	CS	RX	14	NC
SPI Clock	SCK	4	SCK	TX	13	NC
SPI Data OUT	SDO	5	MISO	SCL	12	NC
SPI Data IN	SDI	6	MOSI	SDA	11	NC
Power Supply	3.3V	7	3.3V	5V	10	5V	Power Supply
Ground	GND	8	GND	GND	9	GND	Ground

Onboard settings and indicators

Led ring R Click electrical specifications

Software Support

We provide a library for the Led ring R Click as well as a demo application (example), developed using MIKROE compilers. The demo can run on all the main MIKROE development boards.

Package can be downloaded/installed directly from NECTO Studio Package Manager (recommended), downloaded from our LibStock™ or found on Mikroe github account.

Library Description

This library contains API for Led ring R Click driver.

Key functions

• Generic write function.

• Turn On LED by position.

• Set led.

Example Description

LED ring R click is a mikroBUS™ add-on board with a ring of 32 red LEDs driven.

 void application_task ( void ) 
 { 
     uint32_t ring_led_on = 0x00000001; 
     uint8_t ring_led_counter; 
     uint8_t number_led; 

     ledringr_led_ring_set( &ledringr ); 

     for ( ring_led_counter = 32; ring_led_counter > 0; ring_led_counter--) 
     { 
         ledringr_turn_on_led( &ledringr, ring_led_counter ); 
         Delay_100ms( ); 
     } 

     Delay_100ms( ); 

     while ( ring_led_on < 0xFFFFFFFF ) 
     { 
         ledringr_write_data( &ledringr, ring_led_on ); 
         ring_led_on = ring_led_on | (ring_led_on << 1); 
         Delay_100ms( ); 
     } 
     ledringr_write_data( &ledringr, ring_led_on ); 

     while ( ring_led_on > 0x00000001 ) 
     { 
         ledringr_write_data( &ledringr, ring_led_on ); 
         ring_led_on = ring_led_on >> 1; 
         Delay_100ms( ); 
     } 
     ledringr_write_data( &ledringr, ring_led_on ); 

     Delay_100ms( ); 

     ring_led_on = 0x11111111; 
     for ( ring_led_counter = 0; ring_led_counter < 32; ring_led_counter++ ) 
     { 
         ledringr_write_data( &ledringr, ring_led_on ); 

         ring_led_on *= 2; 

         if ( ring_led_on == 0x88888888 ) 
         { 
             ring_led_on = 0x11111111; 
         } 

         Delay_100ms( ); 
     } 

     for ( ring_led_counter = 0; ring_led_counter < 16; ring_led_counter++ ) 
     { 
         ledringr_write_data( &ledringr, 0xAAAAAAAA ); 
         Delay_100ms( ); 

         ledringr_write_data( &ledringr, 0x55555555 ); 
         Delay_100ms( ); 
     } 

     ledringr_led_ring_reset( &ledringr ); 

     Delay_1sec( ); 
 }

The full application code, and ready to use projects can be installed directly from NECTO Studio Package Manager (recommended), downloaded from our LibStock™ or found on Mikroe github account.

Other Mikroe Libraries used in the example:

• MikroSDK.Board
• MikroSDK.Log
• Click.LedringR

Additional notes and informations

Depending on the development board you are using, you may need USB UART click, USB UART 2 Click or RS232 Click to connect to your PC, for development systems with no UART to USB interface available on the board. UART terminal is available in all MIKROE compilers.

mikroSDK

This Click board™ is supported with mikroSDK – MIKROE Software Development Kit. To ensure proper operation of mikroSDK compliant Click board™ demo applications, mikroSDK should be downloaded from the LibStock and installed for the compiler you are using.

For more information about mikroSDK, visit the official page.