package Top where

import FIFOF
import GetPut
import Uart

interface Top =
  -- RS232
  rx :: Bit 1 -> Action {-# always_enabled, always_ready, prefix = "", arg_names = [RX] #-}
  tx :: Bit 1 {-# always_ready, result = TX #-}
  -- Onboard LEDs
  ledR_N :: Bit 1 {-# always_ready, result = LEDR_N #-}
  ledG_N :: Bit 1 {-# always_ready, result = LEDG_N #-}
  -- RGB LED driver
  ledRed_N :: Bit 1 {-# always_ready, result = LED_RED_N #-}
  ledGrn_N :: Bit 1 {-# always_ready, result = LED_GRN_N #-}
  ledBlu_N :: Bit 1 {-# always_ready, result = LED_BLU_N #-}
  -- LEDs and buttons (PMOD 2)
  led1 :: Bit 1 {-# always_ready, result = LED1 #-}
  led2 :: Bit 1 {-# always_ready, result = LED2 #-}
  led3 :: Bit 1 {-# always_ready, result = LED3 #-}
  led4 :: Bit 1 {-# always_ready, result = LED4 #-}
  led5 :: Bit 1 {-# always_ready, result = LED5 #-}
  btn1 :: Bit 1 -> Action {-# always_enabled, always_ready, prefix = "", arg_names = [BTN1] #-}
  btn2 :: Bit 1 -> Action {-# always_enabled, always_ready, prefix = "", arg_names = [BTN2] #-}
  btn3 :: Bit 1 -> Action {-# always_enabled, always_ready, prefix = "", arg_names = [BTN3] #-}

clockFreqHz :: Integer
clockFreqHz = 12_000_000

mkTop :: Module Top
mkTop =
  module
    bitState :: Reg (Bit 1) <- mkReg 0
    btn2State :: Reg (Bit 1) <- mkReg 0
    btn3State :: Reg (Bit 1) <- mkReg 0

    uart <- mkUart (clockFreqHz / 9600)

    lastByte :: Reg (Bit 8) <- mkReg 0x21
    tick <- mkDivider (clockFreqHz / 2)
    rules
      -- "tick": when tick.clk ==> do
        -- uart.send.put lastByte
      "debugPin": when True ==> bitState := uart.debugPin
      "recv": when True ==> do
        byte <- uart.recv.get
        -- lastByte := byte
        uart.send.put byte
      -- "inc": when tick.clk, btn2State == 1 ==> lastByte := lastByte + 1
      -- "dec": when tick.clk, btn3State == 1 ==> lastByte := lastByte - 1

    interface Top
      -- RS232
      rx bit = do
        uart.rxPin bit
      tx = uart.txPin
      -- Onboard LEDs
      ledR_N = uart.txPin
      ledG_N = bitState
      -- RGB LED driver
      ledRed_N = 1
      ledGrn_N = 1
      ledBlu_N = 1
      -- LEDs and buttons (PMOD 2)
      led1 = 0
      led2 = 0
      led3 = 0
      led4 = 0
      led5 = 0
      btn1 1 = lastByte := 0x40
      btn1 0 = return ()
      btn2 b = btn2State := b
      btn3 b = btn3State := b
{-# verilog mkTop #-}
{-# properties mkTop = { RSTN = BTN_N } #-}

-- vim: set ft=haskell :