
Data send-receive by IIC-bus Hardware: IIC-board with 4 x PCF8574 IC you see a 8bit leds this leds show the value from an other 8574 who has 8 switches as input The 8xswitches from IIC you can see also at the pins PC_0 to PC_7
Dependencies: mbed
Fork of Nucleo_IIC_2x8574in_out by
Gerhard Neumaier will show you :
You can see my hardware: Nucleo F103RB with a IIC-bus application
In the background a printed board "IIC-Trainer" with different IIC ICs like PCF8574a, PCF8591, EEPROM; Real-time-clock In the foreground you see right a own-made printed circuit-board with 4x IC PCF8574
Eine Seite auf os_mbed ARM von Gerhard Neumaier Offenburg Feb 2018
Diff: main.cpp
- Revision:
- 1:cb8a26c1d6e9
- Parent:
- 0:b183e63b31f8
--- a/main.cpp Fri Aug 21 11:40:23 2015 +0000 +++ b/main.cpp Fri Dec 15 11:25:59 2017 +0000 @@ -9,7 +9,7 @@ #include "mbed.h" #define PCF8574_ADDRoutput 0x46 // PCF8574 address 0x46 lowest bit (R/W)=0 IICboard P3 -#define PCF8574_ADDRinput 0x45 // PCF8574 address 0x44 lowest bit (R/W)=0 IICboard P2 +#define PCF8574_ADDRinput 0x45 // PCF8574 address 0x45 lowest bit (R/W)=1 IICboard P2 //ADR-Jumper on IIC4xPCF8574board jumped to 0: Basis ADR:P0=0x40;P1=0x42;P2=0x44;P3=0x46; //ADR-Jumper on IIC4xPCF8574board jumped to 1: Basis ADR:P0=0x48;P1=0x4A;P2=0x4C;P3=0x4E; #define LED_MASK 0xffff //Portc has 16bit, therefore 4digit mask @@ -27,14 +27,14 @@ int main() { char input8bit; - char data_write[2]; //must be char!! - char data_read[2]; //read buffer + char data_write[2]; //must be char!! a array with 2storage places + char data_read[2]; //read buffer a array with 2storage places data_write[0] = 0xf2; //LEDs low aktiv dummy int status = i2c.write(PCF8574_ADDRoutput , data_write, 1, 0); - if (status != 0) // Error no acknowledge detected + if (status != 0) // Error -> no acknowledge detected { - while (1) //-> endless loop when error no IIC-IC detected + while (1) //-> endless loop when error IIC detected { myled = !myled; wait(0.7);