When I initial the I2C module, I run the program step by step, observe the I2C registers.
I notice that the "I2C_2.IBCR.B.MSSL" bit is always 0 and "I2C_2.IBDR.R" is also always 0.
When I run the code "I2C_2.IBCR.B.MSSL = 1;", why will bit "I2C_2.IBSR.B.IBIF" and "I2C_2.IBSR.B.IBAL" turn to 1? instead of bit ""I2C_2.IBCR.B.MSSL" turn to 1?
Is it that I cannnot select master mode, so I cannot set the "I2C_2.IBDR.R"?
// I2C Bus Frequency Divider Register (I2C_IBFD)
I2C_2.IBFD.B.IBC = 0x20; // Division ratio to obtain SCL frequency from Platform clock/2.
// I2C Bus Control Register (I2C_IBCR)
I2C_2.IBCR.B.MDIS = 0; // Enable I2C module
I2C_2.IBCR.B.IBIE = 1; // Interrupts from the I2C Bus module are enabled
I2C_2.IBCR.B.TXRX = 1; // Transmit Mode
// Start I2C master mode transmit
I2C_2.IBCR.B.MSSL = 1; // Master Mode - When this bit is changed from 0 to 1, a START signal is generated on the bus and the master mode is selected
I2C_2.IBSR.B.IBIF = 0; // I-Bus Interrupt Flag
I2C_2.IBDR.R = 0x55; // Sent out 0x55
// Observe changes in IBSR[TCF]
// while (I2C_0.IBSR.B.TCF == 0);
//Wait until IBSR[IBIF] = 1.
while(I2C_2.IBSR.B.IBIF == 0);
I2C_2.IBCR.B.MSSL = 0; // Generate stop signal;
Original Attachment has been moved to: I2C_Z4_1.zip
All I2C modules can work as master. You have to configure pads properly.
Both pins, SDA and SCL, must be configured to enable output buffer, select open-drain function, enable input buffer, select intenal pull ups if there are no external one.
This config can be used:
SIUL2.MSCR.R = 0x23880002; //PE - I2C_2 SCL
SIUL2.IMCR[781-512].R = 1;
SIUL2.MSCR.R = 0x23880004; //PE - I2C_2 SDA
SIUL2.IMCR[782-512].R = 1;