I2C.zip_it

/*---------------------------------------------------------------------------------------------------------*/ /* */ /* Copyright(c) 2014 Nuvoton Technology Corp. All rights reserved. */ /* */ /*---------------------------------------------------------------------------------------------------------*/ //*********************************************************************************************************** // Nuvoton Technology Corp. // E-Mail: MicroC-8bit@nuvoton.com // Date: 27/Jan/2014 //*********************************************************************************************************** /*=========================================================================================================== // N79E352 I2C sample code for I2C Master device, the slave address = 0xA4 // // ____________ _____________ // | | SDA | | // | |<-------->| | // | | | | // | N79E352(M) | | N79E352(S) | // |(I2C_Master)| | (I2C_Slave) | // | | SCL | | // | |--------->| | // |____________| |_____________| // // The transaction protocol: // S => SLA+W(A) => DATA_AMOUNT(A) => Data[0](A) => Data[1](A) => ... => Data[6](A) => Data[7](/A) => P // S => SLA+W(A) => DATA_ADDR(A) => rS => SLA+R(A) => Read_Back_Data(A) => P // // Suggest observing SDA and SCL waveform with an oscilloscope. *=========================================================================================================*/ /* //-------- <<< Use Configuration Wizard in Context Menu >>> ------------------ // // <o0> I2C clock rate under Fsys 22.1184MHz // <13=> 400kbps // <54=> 100kbps // <o5> Data which is wanted to be read back // <0=> Byte 0, 0x00 // <1=> Byte 1, 0x55 // <2=> Byte 2, 0xAA // <3=> Byte 3, 0xFF // <4=> Byte 4, 0x54 // <5=> Byte 5, 0xA9 // <6=> Byte 6, 0xFE // <7=> Byte 7, 0x53 // //-------- <<< end of configuration section >>> ------------------------------ */ #include "N79E352.h" #include "Typedef.h" #define I2C_CLOCK 13 #define SLAVE_ADDRESS 0xA4 //for I2C Slave MCU address #define WR 0 //WR and RD determine SLA+W or SLA+R #define RD 1 #define DATA_AMOUNT 8 //8 byte data length for demo #define DATA_INDEX 0 #define ERROR_CODE 0x78 #define PASS_CODE 0x5d const UINT8 Data[DATA_AMOUNT] = {0x00, 0x55, 0xAA, 0xFF, 0x54, 0xA9, 0xFE, 0x53}; volatile UINT8 u8Data_Num = 0, u8Read_Back_Data; volatile BIT bWR_RD = WR; /************************************************************************************************************ * I2C interrupt subroutine ************************************************************************************************************/ void I2C_Error (void) { P0 = ERROR_CODE; while(1); } /************************************************************************************************************ * I2C interrupt subroutine ************************************************************************************************************/ void I2C_ISR (void) interrupt 6 //interrupt address is 0x0033 { switch (I2STATUS) { case 0x00: //bus error handle STO = 1; SI = 0; while(STO); ENSI = 0; ENSI = 1; break; case 0x08: STA = 0; I2DAT = SLAVE_ADDRESS + WR; break; case 0x10: STA = 0; I2DAT = SLAVE_ADDRESS + RD; break; case 0x18: I2DAT = (!bWR_RD) ? DATA_AMOUNT : DATA_INDEX; break; case 0x28: if (!bWR_RD) { I2DAT = Data[u8Data_Num]; u8Data_Num++; } else STA = 1; break; case 0x30: STO = 1; u8Data_Num = 0; bWR_RD = RD; break; case 0x40: AA = 1; break; case 0x50: u8Read_Back_Data = I2DAT; STO = 1; bWR_RD = WR; break; case 0x20: case 0x38: case 0x48: case 0x58: case 0x68: case 0x78: case 0xB0: P2 = I2STATUS; I2C_Error(); break; } SI = 0; while(STO); } /************************************************************************************************************ * Main function ************************************************************************************************************/ void main (void) { UINT8 u8Delay = 0xFF; P12 = P13 = 1; //before use I2C bus, function shared pins P1.2 and P1.3 should be high I2CLK = I2C_CLOCK; //determine I2C clock rate ENSI = 1; //enable I2C EI2 = 1; EA = 1; while (u8Delay--); //short delay to waiting I2C slave device ready STA = 1; //generate START condition to start writing transaction while(!bWR_RD); //waiting for writing transaction complete STA = 1; //generate START condition to start reading transaction while(bWR_RD); //waiting for reading transaction complete /*check read back data value*/ if (u8Read_Back_Data != Data[DATA_INDEX]) I2C_Error(); else P0 = PASS_CODE; while(1); }