Subversion Repositories wb_lcd

from myhdl import *

t_TxState = enum('tx_high_setup', 'tx_high_hold', 'tx_oneus', 'tx_low_setup', 'tx_low_hold', 'tx_fortyus', 'tx_done');
t_State = enum('display_init', 'init_fifteenms', 'init_one', 'init_two', 'init_three', 'init_four', 'init_five', 'init_six', 'init_seven', 'init_eight', 'display_function_set', 'display_entry_set', 'display_set_display', 'display_clr_display', 'display_pause_setup', 'display_pause', 'display_set_addr1', 'display_char_write1', 'display_set_addr2', 'display_char_write2','display_done')

def delayCounter(clk, reset, count, load, done, width = 13):
    
    counter = Signal(intbv(0)[width:0])

    @always_comb
    def done_logic():
        done.next = (counter == 0)
            
    @always(clk.posedge)
    def countdown_logic():
        if load:
            counter.next = count
        else: #elif not done:
            counter.next = counter - 1
        
    return instances()
        
        

def lcd(clk, reset, dat, addr, we, repaint, busy, SF_D, LCD_E, LCD_RS, LCD_RW):
    
    
    state = Signal(t_State.display_init)
    tx_state = Signal(t_TxState.tx_done)
    tx_byte = Signal(intbv(0)[8:0])
    tx_init = Signal(bool())
    tx_done = Signal(bool())
    LCD_E0 = Signal(bool())
    SF_D0 = Signal(intbv(0)[4:0])
    LCD_E1 = Signal(bool())
    SF_D1 = Signal(intbv(0)[4:0])
    pos = Signal(intbv(0)[7:0])
    MEM_LOW1 =0
    MEM_LOW2 =15
    MEM_HIGH1 =40
    MEM_HIGH2 =55

    @always_comb
    def busy_and_rw_handlers():
        busy.next = (state != t_State.display_done)
        LCD_RW.next = 0
        
    # Memory interface
    ram = [Signal(intbv(0)[31:0]) for i in range(67)]

    @always(clk.posedge)
    def memWrite():
        if we:
            ram[int(addr)].next = dat

              
    #Delay counter
    main_delay_load = Signal(bool())
    main_delay_value = Signal(intbv(0)[20:0])
    
    tx_delay_load = Signal(bool())
    main_delay_load = Signal(bool())
    delay_load = Signal(bool())
    
    tx_delay_value = Signal(intbv(0)[20:0])
    main_delay_value = Signal(intbv(0)[20:0])
    delay_value = Signal(intbv(0)[20:0])
    
    delay_done = Signal(bool())
    output_selector  = Signal(bool())    
    counter = delayCounter(clk, reset, delay_value, delay_load, delay_done, width = 21)

    @always_comb
    def conunter_sharing_load():
        delay_load.next = tx_delay_load or main_delay_load
            
    @always_comb
    def conunter_sharing_value():
        if tx_delay_load:
            delay_value.next = tx_delay_value 
        else:
            delay_value.next = main_delay_value


    # SF_D and LCD_E management for sharing between Init and TX phases.
    @always_comb
    def output_tx_or_init_select(): # 0 tx; 1 init
        output_selector.next = (state == t_State.display_init) | (state == t_State.init_fifteenms) | (state == t_State.init_one) | (state == t_State.init_two) | (state == t_State.init_three) | (state == t_State.init_four) | (state == t_State.init_five) | (state == t_State.init_six) | (state == t_State.init_seven) | (state == t_State.init_eight) 
        
    @always_comb
    def output_tx_or_init_mux():
        if output_selector: # Init
            SF_D.next = SF_D1
            LCD_E.next = LCD_E1
        else: # TX
            SF_D.next = SF_D0 
            LCD_E.next = LCD_E0 


    @always_comb
    def init_transmissions():
        tx_init.next = (~tx_done) & ((state == t_State.display_function_set) | (state == t_State.display_entry_set) | (state == t_State.display_set_display) | (state == t_State.display_clr_display) | (state == t_State.display_set_addr1) | (state == t_State.display_char_write1) | (state == t_State.display_set_addr2) | (state == t_State.display_char_write2))
        LCD_RS.next = ~(bool(state == t_State.display_function_set) | (state == t_State.display_entry_set) | (state == t_State.display_set_display) | (state == t_State.display_clr_display) | (state == t_State.display_set_addr1) | (state == t_State.display_set_addr2))
        
    @always(clk.posedge, reset.posedge)
    def DisplayFSM():
        if reset == 1:
            state.next = t_State.display_init
            main_delay_load.next = 0
            main_delay_value.next = 0
            SF_D1.next = 0
            LCD_E1.next = 0
            tx_byte.next = 0
        else:
            main_delay_load.next = 0;
            main_delay_value.next = 0;
            if state == t_State.display_init:
                tx_byte.next = 00000000
                
                state.next = t_State.init_fifteenms
                main_delay_load.next = 1
                main_delay_value.next = 750000            
                                                
            elif state == t_State.init_fifteenms:
                main_delay_load.next = 0
                
                if delay_done:
                    state.next = t_State.init_one;
                    main_delay_load.next = 1
                    main_delay_value.next = 11
                    
            elif state == t_State.init_one:
                main_delay_load.next = 0
                SF_D1.next = 3
                LCD_E1.next = 1    
                
                if delay_done:
                    state.next = t_State.init_two;
                    main_delay_load.next = 1
                    main_delay_value.next = 205000

            elif state == t_State.init_two:
                main_delay_load.next = 0
                LCD_E1.next = 0    
                
                if delay_done:
                    state.next = t_State.init_three;
                    main_delay_load.next = 1
                    main_delay_value.next = 11
                
            elif state == t_State.init_three:
                main_delay_load.next = 0
                SF_D1.next = 3
                LCD_E1.next = 1    
                
                if delay_done:
                    state.next = t_State.init_four;
                    main_delay_load.next = 1
                    main_delay_value.next = 5000

            elif state == t_State.init_four:
                main_delay_load.next = 0
                LCD_E1.next = 0    
                
                if delay_done:
                    state.next = t_State.init_five;
                    main_delay_load.next = 1
                    main_delay_value.next = 11
                    

            elif state == t_State.init_five:
                main_delay_load.next = 0
                SF_D1.next = 3
                LCD_E1.next = 1    
                
                if delay_done:
                    state.next = t_State.init_six;
                    main_delay_load.next = 1
                    main_delay_value.next = 2000

            elif state == t_State.init_six:
                main_delay_load.next = 0
                LCD_E1.next = 0   
                
                if delay_done:
                    state.next = t_State.init_seven;
                    main_delay_load.next = 1
                    main_delay_value.next = 11

            elif state == t_State.init_seven:
                main_delay_load.next = 0
                SF_D1.next = 2
                LCD_E1.next = 1    
                
                if delay_done:
                    state.next = t_State.init_eight;
                    main_delay_load.next = 1
                    main_delay_value.next = 2000

            elif state == t_State.init_eight:
                main_delay_load.next = 0
                LCD_E1.next = 0
                
                if delay_done:
                    state.next = t_State.display_function_set;
                    
            elif state == t_State.display_function_set:
                tx_byte.next = 00101000;
                if tx_done:
                    state.next = t_State.display_entry_set

            elif state == t_State.display_entry_set:
                tx_byte.next = 00000110;
                if tx_done:
                    state.next = t_State.display_set_display
                    
            elif state == t_State.display_set_display:
                tx_byte.next = 00001100;
                if tx_done:
                    state.next = t_State.display_clr_display

            elif state == t_State.display_clr_display:
                tx_byte.next = 00000001;
                if tx_done:
                    state.next = t_State.display_pause_setup
                    main_delay_load.next = 1
                    main_delay_value.next = 82000

            elif state == t_State.display_pause_setup:
                state.next = t_State.display_pause
                
            elif state == t_State.display_pause:
                tx_byte.next = 00000000;
                
                if delay_done:
                    state.next = t_State.display_set_addr1;
                    
            elif state == t_State.display_set_addr1:
                tx_byte.next = 00000000;
                if tx_done:
                    state.next = t_State.display_char_write1
                    pos.next = MEM_LOW1
                
            elif state == t_State.display_char_write1:
                tx_byte.next = ram[pos]
                if tx_done:                
                    if pos == MEM_HIGH1:
                        state.next = t_State.display_set_addr1;
                    else:
                        pos.next = pos + 1
            elif state == t_State.display_set_addr2:
                tx_byte.next = 11000000;
                if tx_done:
                    state.next = t_State.display_char_write2
                    pos.next = MEM_LOW2
                
            elif state == t_State.display_char_write2:
                tx_byte.next = ram[pos]
                if tx_done:                
                    if pos == MEM_HIGH2:
                        state.next = t_State.display_done;
                    else:
                        pos.next = pos + 1

            elif state == t_State.display_done:
                tx_byte.next = 00000000;
                
                if repaint:
                    state.next = t_State.display_function_set
                else:
                    state.next = t_State.display_done
                    
            else:
                
                raise ValueError("Undefined Display state")
            
  

    @always(clk.posedge, reset.posedge)
    def TxFSM():
        if reset == 1:
            tx_state.next = t_TxState.tx_done
            SF_D0.next = 0
            LCD_E0.next = 0
        else:
            tx_delay_load.next = 0;
            tx_delay_value.next = 0;
            if tx_state == t_TxState.tx_high_setup:
                LCD_E0.next = 0
                SF_D0.next = tx_byte[8 : 4]
                tx_delay_load.next = 0
                if delay_done:
                    tx_state.next = t_TxState.tx_high_hold
                    tx_delay_load.next = 1
                    tx_delay_value.next = 12
                    
            elif tx_state == t_TxState.tx_high_hold:
                LCD_E0.next = 1
                SF_D0.next = tx_byte[8 : 4]
                tx_delay_load.next = 0
                if delay_done:
                    tx_state.next = t_TxState.tx_oneus
                    tx_delay_load.next = 1
                    tx_delay_value.next = 50
                    
            elif tx_state == t_TxState.tx_oneus:
                LCD_E0.next = 0
                tx_delay_load.next = 0
                if delay_done:
                    tx_state.next = t_TxState.tx_low_setup
                    tx_delay_load.next = 1
                    tx_delay_value.next = 2
                    
            elif tx_state == t_TxState.tx_low_setup:
                LCD_E0.next = 0
                SF_D0.next = tx_byte[4 : 0]
                tx_delay_load.next = 0
                if delay_done:
                    tx_state.next = t_TxState.tx_low_hold
                    tx_delay_load.next = 1
                    tx_delay_value.next = 12
                    
            elif tx_state == t_TxState.tx_low_hold:
                LCD_E0.next = 1
                SF_D0.next = tx_byte[4 : 0]
                tx_delay_load.next = 0
                if delay_done:
                    tx_state.next = t_TxState.tx_fortyus
                    tx_delay_load.next = 1
                    tx_delay_value.next = 2000
                    
            elif tx_state == t_TxState.tx_fortyus:
                LCD_E0.next = 0
                tx_delay_load.next = 0
                if delay_done:
                    tx_state.next = t_TxState.tx_done
                    tx_done.next = 1
                    
            elif tx_state == t_TxState.tx_done:
                LCD_E0.next = 0
                tx_done.next = 0
                tx_delay_load.next = 0
                if tx_init:                
                    tx_state.next = t_TxState.tx_high_setup
                    tx_delay_load.next = 1
                    tx_delay_value.next = 2
            else:
                raise ValueError("Undefined TX state")
            
    return instances()

def main():
    width = 20

    count = Signal(intbv(0)[width:0])
    clk, reset, we, repaint, busy, LCD_E, LCD_RS, LCD_RW = [Signal(bool(0)) for i in range(8)]
    dat = Signal(intbv(0)[32:0])
    addr = Signal(intbv(0)[7:0])
    SF_D = Signal(intbv(0)[4:0])
    
    toVerilog(lcd,clk, reset, dat, addr, we, repaint, busy, SF_D, LCD_E, LCD_RS, LCD_RW)
#    toVHDL(delayCounter, clk, reset, count, load, done, width)    
if __name__ == '__main__':
    main()