hi, Has anybody written ever an user_logic core for some device which is interfaced to a microblaze? I don't know what's wrong with the following: I used the wizard to generate a simple 8 bit led_port core with a few 32 bits registers. In C I write the following: LedPortPtr = (Xuint32 *)XPAR_LED_PORT_0_BASEADDR; while(1){ *(LedPortPtr) = 0xF3111111; //print ("1"); *(LedPortPtr) = 0x0 //print("0"); }
The problem is that if I remove the print statements like above the port doesn't show a square wave on an oscilloscope on one of the outputs. With the print state it does. With a dummy (volatile declared) delay loop it doesn't. Readback of registers works fine.
the user_logic.vhd looks super simple: SLAVE_REG_WRITE_PROC : process( Bus2IP_Clk ) is begin
if Bus2IP_Clk'event and Bus2IP_Clk = '1' then if Bus2IP_Reset = '1' then slv_reg0 '0'); slv_reg1 '0'); slv_reg2 '0'); slv_reg3 '0'); else case slv_reg_write_sel is when "1000" =>