design a ip implements Modbus RTU slave sub function 03 04 06 on FPGA.

Function code: 03 04 06

Exception code: 01 02 03 04

Function 03: ligal reg 0001, ligal quantiy 0001

Function 04: ligal reg 0001~0004, ligal quantiy + ligal reg < 0005

Function 06: ligal reg 0001, ligal data 0000~0017, coresponding to Function 03 reg 0001

slave address assigned by port.

done

uart_byte_tx_tb.do

uart_byte_rx_tb.do

done

ct_35t_gen_tb.do

ct_15t_gen_tb.do

done

frame_rx_tb.do

done

modbus_crc_tb.do

done

exceptions_tb.do

done

func_handler_tb.do

done

tx_response_tb.do

tx_response_tb.do

assign code 03 reg 0001 value 0451

response is ok

here 06 dosen't have reg 0002, so it's illegal

response is ok

read 4 regs from 0001

response is ok

after a write fail

response is ok

response is ok

done

modbus_rtu_slave_top_tb.do