mem_data_in ----------------------o-------,
                                  |       |
                                  |   +---+--+
                                  |   |  IR  |<---- ir_en
                                  |   +---+--+
                                  |       '-------- ir
                                  |
  ,---------------------------,   |   ,-----------------------------------,
  |                           |   |   |                                   |
  |                        ---+---+---+---                                |
  |                        \  2   1   0  /                                |
  |                         \           /<--- regbank_mux_sel             |
  |                          \_________/                                  |
  |                               |                                       |
  |                               |                                       |
  |              +----------------+----------------+                      |
  |              |             i_data              |<--- i_sel            |
  |              |                                 |<--- i_en             |
  |              |          Register Bank          |<--- mode             |
  |              |                                 |<--- oa_sel           |
  |              |   pc     oa             ob      |<--- ob_sel           |
  |              +---+-------+--------------+------+                      |
  |                  |       |              |   ,------- Immediate        |
  |      ,-----------)-------o           ---+---+---                      |
  |      | backup_en |       |           \  1   0  /                      |
  | +----+---+  |    |       |            \       /<---- shifter_mux_sel  |
  | | backup |<-'    |       |             \_____/                        |
  | +----+---+       |       |                |   shifter_amount_immediate|
  '------o-----------)-------)----------------)---------,   |             |
         |           |       |                |      ---+---+---          |
         |           |       |                |      \  1   0  /  shifter_|
         |           |       |                |       \       /<- amount_ |
         |           |       |            ----+------  \_____/    mux_sel |
         |           |       |           /          /<----'               |
         |           |       |          /  Shifter /<--- shifter_carry_in |
         |           |       |         /  out     /<---- shifter_opcode   |
         |           |       |        /__________/--,                     |
         |           |       |             |        | shifter_carry_out   |
         |           | ------+----.  ,-----+-----   |                     |
         |           | \     a     \/      b   /<---'                     |
         |           |  \         ALU         /<----- alu_c_flag_in       |
         |           |   \                   /<------ alu_v_flag_in       |
         |           |    \      result     /<------- alu_opcode          |
         |           |     \_______________/--------> alu_{n,z,c,f}_out   |
         |           |             |                                      |
         |           |             o--------------------------o-----------'
         |           |             |                          |
         |           |        +----+----+                     |
         |           |        | address |<--- address_en      |
         |           |        +----+----+                     |
         |           '---------,   |                          |
         '-----------------,   |   |                          |
                           |   |   |                          |
                        ---+---+---+---                       |
                        \  2   1   0  /                       |
                         \           /<---- mem_addr_mux_sel  |
                          \____+____/                         |
                               |                              |
                           mem_addr                     mem_data_out