Nowadays, I am trying to add a new core "I2C controller core" which written by Richard.

What I have done is:

1, make changes in minsoc_defines.v.

"`define APP_ADDR_I2C `APP_ADDR_DEC_W'h9d"
"`define APP_INT_I2C 3"

2. make changes in "module minsoc_top ()"
~build tri-state
`ifdef I2C
assign scl = scl_en_o ? 1'bz : scl_o;
assign sda = sda_en_o ? 1'bz : sda_o;
assign scl_i = scl;
assign sda_i = sda;
`endif

~Instantiation of the I2C

~ I2C added to minsoc_tc_top (target 4)

and I wrote a test program

int main()
{

uart_init();

REG8(I2C_BASE + I2C_PRESC_HI)= 0xff;
REG8(I2C_BASE + I2C_PRESC_LO)= 0xff;

REG8(I2C_BASE+I2C_CTR) = I2C_CTR_EN | I2C_CTR_IRQ_EN;
uart_print_short(REG8(I2C_BASE+I2C_CTR));


report(0xdeaddead);
or32_exit(0);
}

I found the result is 0x0. Besides, whatever written into the registers which is RW, the reading out result is 0x0. Using gdb, the registers value is void("").

The way how I add the I2C core is similar with UART core.

I don't know whether anyone can give me some advices. Thank you for your reply.

Hi,

I used the I2C core on minsoc extensively already. In the following I will give you an insight of my changes in order to do so:

Since there is already a driver for using I2C and the firmware configuration expects the core to be on address 9d, I'd recommend you to switch
`define APP_ADDR_AUDIO `APP_ADDR_DEC_W'h9d to
`define APP_ADDR_I2C `APP_ADDR_DEC_W'h9d

also switch:
`define APP_INT_RES2 3 to
`define APP_INT_I2C 3

Then, patch minsoc_top.v with the attached patch (i2c_patch). You will also need the minsoc_wb_32_8_bridge.v Verilog file under minsoc/utils to synthesize or simulate this design.

Attached you also find an example firmware (i2capp.c) working with i2c through the i2c driver found under minsoc/sw/drivers/i2c.c.

I hope that helps and let us know how far you get.
Raul

Thank you very much! The registers can be written and read now.

I did not use minsoc_wb_32_8_bridge.v Verilog file.

I suppose the width of data and address are not 32bits.

So they can not be connected to wishbone interface directly.

Thanks again!