These are interesting modules that you can buy from various online sources. They comprise of 2 4×7 7 Segment displays, 8 push buttons and 8 LEDs. The chip that performs all the magic is a TM1638.
The module I bought had 5 connections.
VCC – 5v
Gnd – GND
STB – strobe pin
CLK – clock pin
DIO – data pin
Schematic
The board I used had a PIC 18F4550 on it
If you are interested the board is available from (UK) – RKPK40 Prototype PCB for 40 pin PIC
In the code example later you can see the pins used, they are pins 5, 6 and 7 on PORTB
#define DI PORTB.F5
#define CLK PORTB.F6
#define STB PORTB.F7
Code
This was a MIKROC example – https://libstock.mikroe.com/projects/view/2120/tm1638-led-amp-key
[codesyntax lang=”cpp”]
///////////////////////////////////////////////////////
// //
// TM1638 LED&KEY module //
// MikroC for PIC //
// //
///////////////////////////////////////////////////////
//PIC 12
//#define DI GPIO.F2
//#define DO TRISIO.F2
//#define CLK GPIO.F1
//#define STB GPIO.F0
// PIC 16
//#define DI PORTB.F5
////#define DO TRISB.F5
//#define CLK PORTB.F6
//#define STB PORTB.F7
//PIC 18
#define DI PORTB.F5
#define DO LATB.F5
#define CLK PORTB.F6
#define STB PORTB.F7
///////////////////////////////////////////////////////
// //
// 7 Segment common Cathode HGFEDCBA codes //
// code, // number description //
// //
///////////////////////////////////////////////////////
const char FontNumber[] =
{
0x3F, // 0 0
0x06, // 1 1
0x5B, // 2 2
0x4F, // 3 3
0x66, // 4 4
0x6D, // 5 5
0x7D, // 6 6
0x07, // 7 7
0x7F, // 8 8
0x6F, // 9 9
0x77, // 10 A
0x7C, // 11 B
0x39, // 12 C
0x5E, // 13 D
0x79, // 14 E
0x71, // 15 F
0x3D, // 16 G
0x76, // 17 H
0x00, // 18
0x40, // 19 -
0x80, // 20 .
0x63, // 21 *
0x78, // 22 t
0x1E, // 23 J
0x38, // 24 L
};
const char FontChar[] =
{
0b00000000, // (32) <space>
0b10000110, // (33) !
0b00100010, // (34) "
0b01111110, // (35) #
0b01101101, // (36) $
0b00000000, // (37) %
0b00000000, // (38) &
0b00000010, // (39) '
0b00110000, // (40) (
0b00000110, // (41) )
0b01100011, // (42) *
0b00000000, // (43) +
0b00000100, // (44) ,
0b01000000, // (45) -
0b10000000, // (46) .
0b01010010, // (47) /
0b00111111, // (48) 0
0b00000110, // (49) 1
0b01011011, // (50) 2
0b01001111, // (51) 3
0b01100110, // (52) 4
0b01101101, // (53) 5
0b01111101, // (54) 6
0b00100111, // (55) 7
0b01111111, // (56) 8
0b01101111, // (57) 9
0b00000000, // (58) :
0b00000000, // (59) ;
0b00000000, // (60) <
0b01001000, // (61) =
0b00000000, // (62) >
0b01010011, // (63) ?
0b01011111, // (64) @
0b01110111, // (65) A
0b01111111, // (66) B
0b00111001, // (67) C
0b00111111, // (68) D
0b01111001, // (69) E
0b01110001, // (70) F
0b00111101, // (71) G
0b01110110, // (72) H
0b00000110, // (73) I
0b00011111, // (74) J
0b01101001, // (75) K
0b00111000, // (76) L
0b00010101, // (77) M
0b00110111, // (78) N
0b00111111, // (79) O
0b01110011, // (80) P
0b01100111, // (81) Q
0b00110001, // (82) R
0b01101101, // (83) S
0b01111000, // (84) T
0b00111110, // (85) U
0b00101010, // (86) V
0b00011101, // (87) W
0b01110110, // (88) X
0b01101110, // (89) Y
0b01011011, // (90) Z
0b00111001, // (91) [
0b01100100, // (92) \ (this can't be the last char on a line, even in comment or it'll concat)
0b00001111, // (93) ]
0b00000000, // (94) ^
0b00001000, // (95) _
0b00100000, // (96) `
0b01011111, // (97) a
0b01111100, // (98) b
0b01011000, // (99) c
0b01011110, // (100) d
0b01111011, // (101) e
0b00110001, // (102) f
0b01101111, // (103) g
0b01110100, // (104) h
0b00000100, // (105) i
0b00001110, // (106) j
0b01110101, // (107) k
0b00110000, // (108) l
0b01010101, // (109) m
0b01010100, // (110) n
0b01011100, // (111) o
0b01110011, // (112) p
0b01100111, // (113) q
0b01010000, // (114) r
0b01101101, // (115) s
0b01111000, // (116) t
0b00011100, // (117) u
0b00101010, // (118) v
0b00011101, // (119) w
0b01110110, // (120) x
0b01101110, // (121) y
0b01000111, // (122) z
0b01000110, // (123) {
0b00000110, // (124) |
0b01110000, // (125) }
0b00000001, // (126) ~
};
void Write1638(unsigned char Data)
{
unsigned char i;
for(i=0 ; i<8 ; i++)
{
DI = (Data & 0x01);
CLK = 0;
Data >>= 1;
CLK = 1;
}
}
void WriteCmd(unsigned char cmd)
{
STB = 0;
Write1638(cmd);
STB = 1;
}
///////////////////////////////////////////////////////
// //
// Read buttons //
// 1F 17 0F 07 1B 13 0B 03 //
// //
///////////////////////////////////////////////////////
unsigned char ReadKey(void)
{
unsigned char i;
unsigned char temp=32;
STB = 0;
Write1638(0x42); // Switch to read mode
DO = 1; // Set DIO = input
for(i=0; i<32; i++) // Read 4 bytes
{
temp--;
CLK = 0;
delay_us(1); // Fast MCU (>4MHz)
if(DI)
temp<<=1;
CLK = 1;
}
DO = 0; // Set DIO = output
STB = 1;
return temp; // 0x00 ~ 0xFF
}
void WriteData(unsigned char Adress,unsigned char Data)
{
WriteCmd(0x44);
STB = 0;
Write1638(0xC0 | Adress);
Write1638(Data);
STB = 1;
}
///////////////////////////////////////////////////////
// //
// Clear display, turn leds off //
// //
///////////////////////////////////////////////////////
void LedReset (void)
{
unsigned char i;
CLK = 1;
WriteCmd(0x40);
STB = 0;
Write1638(0xC0);
for(i=0 ; i<32 ; i++)
{
Write1638(0x00);
}
STB = 1;
CLK = 1;
}
///////////////////////////////////////////////////////
// //
// Led - positions 1,3,5,7,9,11,13,15 //
// 0 - turn led ON, 1 - turn OFF //
// 7Seg - positions 0,2,4,6,8,10,12,14 //
// //
///////////////////////////////////////////////////////
void WriteDigit(char number,char pos)
{
WriteCmd(0x44);
STB = 0;
Write1638(0xC0 | pos);
Write1638(FontNumber[number]);
STB = 1;
}
void DisplayLongNumber(signed long number)
{
unsigned char und,dec,cnt,mil,decmil,cntmil,mlh,decmlh;
signed long tmp;
und = number%10;
tmp = number/10;
dec = tmp%10;
tmp = tmp/10;
cnt = tmp%10;
tmp = tmp/10;
mil = tmp%10;
tmp = tmp/10;
decmil = tmp%10;
tmp = tmp/10;
cntmil = tmp%10;
tmp = tmp/10;
mlh = tmp%10;
tmp = tmp/10;
decmlh = tmp%10;
CLK = 1;
WriteCmd(0x40);
STB = 0;
Write1638(0xC0);
Write1638(FontNumber[decmlh]);
Write1638(0x00);
Write1638(FontNumber[mlh]);
Write1638(0x00);
Write1638(FontNumber[cntmil]);
Write1638(0x00);
Write1638(FontNumber[decmil]);
Write1638(0x00);
Write1638(FontNumber[mil]);
Write1638(0x00);
Write1638(FontNumber[cnt]);
Write1638(0x00);
Write1638(FontNumber[dec]);
Write1638(0x00);
Write1638(FontNumber[und]);
Write1638(0x00);
STB = 1;
CLK = 1;
}
void DisplayString(const char *msg)
{
CLK = 1;
WriteCmd(0x40);
STB = 0;
Write1638(0xC0);
Write1638(FontChar[msg[0]-32]);
Write1638(0x00);
Write1638(FontChar[msg[1]-32]);
Write1638(0x00);
Write1638(FontChar[msg[2]-32]);
Write1638(0x00);
Write1638(FontChar[msg[3]-32]);
Write1638(0x00);
Write1638(FontChar[msg[4]-32]);
Write1638(0x00);
Write1638(FontChar[msg[5]-32]);
Write1638(0x00);
Write1638(FontChar[msg[6]-32]);
Write1638(0x00);
Write1638(FontChar[msg[7]-32]);
Write1638(0x00);
STB = 1;
CLK = 1;
}
void main(void)
{
//TRISIO = 0x00;
//GPIO = 0x00;
//ANSEL = 0x00; // AD Disabled
TRISA = 0x00;
TRISB = 0x00;
TRISC = 0x00;
//TRISD = 0x00;
PORTA = 0x00;
PORTB = 0x00;
PORTC = 0x00;
//PORTD = 0x00;
ADCON0 = 0x00; // AD Disabled
ADCON1 = 0x06; // All inputs are digital
//T0CON = 0x00;
//INTCON = 0x00;
//INTCON2 = 0x00;
//CMCON = 0x07; // Compare disabled
delay_ms(1000); // Power-Up recovery delay
WriteCmd(0x8F); // Light level (8,9,A,B,C,D,E,F)
LedReset();
///////////////////////////////////////////////////////
// //
// DEMO TEST //
// //
///////////////////////////////////////////////////////
while(1)
{
DisplayLongNumber(76543210);
delay_ms(2000);
DisplayString("--OFF---");
delay_ms(1000);
WriteCmd(0x80); // Display off
delay_ms(1000);
WriteCmd(0x88); // Light min
DisplayString("-LLL-001");
delay_ms(1000);
WriteCmd(0x8B);
DisplayString("-LLL-004");
delay_ms(1000);
WriteCmd(0x8F); // Light max
DisplayString("-LLL-008");
delay_ms(1000);
LedReset();
delay_ms(1000);
WriteDigit (0,1); // Leds...
WriteDigit (10,0);
delay_ms(200);
WriteDigit (0,3);
WriteDigit (11,2);
delay_ms(200);
WriteDigit (0,5);
WriteDigit (12,4);
delay_ms(200);
WriteDigit (0,7);
WriteDigit (13,6);
delay_ms(200);
WriteDigit (0,9);
WriteDigit (14,8);
delay_ms(200);
WriteDigit (0,11);
WriteDigit (15,10);
delay_ms(200);
WriteDigit (0,13);
WriteDigit (16,12);
delay_ms(200);
WriteDigit (0,15);
WriteDigit (17,14);
delay_ms(2000);
{ // Keys test
unsigned char i;
for(i=0 ; i<100 ; i++)
{
DisplayLongNumber(ReadKey());
delay_ms(200);
}
}
DisplayString("SOFt OFF");
delay_ms(1000);
LedReset();
delay_ms(1000);
}
}
[/codesyntax]
Links
1pc Key Display For AVR Arduino New 8-Bit Digital LED Tube 8-Bit TM1638 Module