Simple LED CLOCK using Raspberry Pi PICO

PicoClock.bas

'==============================================================================
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' TTTTT M   M   1    666  3333  77777       BBBB   AAA   SSSS
'   T   MM MM  11   6         3    7        B   B A   A S
'   T   M M M   1   6666   333    7         BBBB  AAAAA  SSS
'   T   M M M   1   6   6     3  7     ..   B   B A   A     S
'   T   M   M  111   666  3333  7      ..   BBBB  A   A SSSS
'==============================================================================
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'==============================================================================
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' Program:      TM1637.BAS
' Author:       Pete Willard
' Version:      1.0
' Target:       PICOMITE
' Date:         2022/06/07
' Time:         17:27:30
' Notes:        Much help from Pete Maher
'
' Reference:  TM1637 DATASHEET IN WONDERFUL CHINGLISH.
' It kind of wants to be true SPI and then it doesn't feel like it so much.
' It's really just simpler "shift register" stuff.  The TM1637 treats these
' as open collector, to pullups resistors are used to pull the pins to Vcc.
' The board has the following pins:
'   CLK, DIO, GND AND 5V
' Pull DIO low before CLK transition to create a START condition
' Pull CLK high before DIO after and 8 bit data transfer to signal
' END condition
' There are 3 basic command modes:
' DISPLAY ON/OFF    &H8F/&H80
' DATA WRITE        &H40/&H44
' WRITE TO REGISTER &HC0/&HC1...
'
'==============================================================================
' MMBASIC CLOCK
'--------------
'OPTION SYSTEM SPI GP18,GP19,GP16
'OPTION SYSTEM I2C GP0,GP1
'OPTION AUTORUN 1
'OPTION COLOURCODE ON
'OPTION SDCARD GP22
  -----------------------------
  
'=====[ CONFIGURATION ]========================================================
  Option explicit
  Option default none
  
'=====[ VARIABLES ]============================================================
  Dim  digittosegment%(15)=(&H3F,&H06,&H5B,&H4F,&H66,&H6D,&H7D,&H07,&H7F,&H6F,&H7
  PRESS ANY KEY ...                 7,&H7C,&H39,&H47,&H79,&H71)
  Dim integer m_brightness ' 0-15
  Dim integer displaydata(3)=(0,0,0,0) ' Holds segment data for digits
  Const false=0
  Const true=1
  Const colon=1
  Const nocolon=0
  Const noleadingzeros=1
  Const leadingzeros=0
  Const TM1637_I2C_COMM1 =  &H40
  Const TM1637_I2C_COMM2 =  &HC0
  Const TM1637_I2C_COMM3 =  &H80
'
  
  Dim mytime$ length 8
'=====[ PINS ]=================================================================
  Dim INTEGER DIO = 17    ' GPIO 12
  Dim INTEGER CLK = 16    ' GPIO 13
'=====[ SUBROUTINES ]==========================================================
Sub TM1637Init(pinClk As integer, pinDIO As integer)
  Dim integer m_pinClk,m_pinDIO
  PRESS ANY KEY ...                  ' Copy the pin numbers
  m_pinClk = pinClk
  m_pinDIO = pinDIO
  
' Set the pin direction and default value.
' Both pins are set as inputs, allowing the pull-up resistors to pull them up
  Pin(m_pinDIO)=0
  Pin(m_pinClk)=0
  SetPin m_pinDIO,DIN
  SetPin m_pinClk,DIN
End Sub
'=============================================
Sub setBrightness(brightness As integer)
  m_brightness = brightness
End Sub
'=============================================
Sub setSegments(segments() As integer)
  Local integer k
' Write COMM1
  sendstart
  writeByte(TM1637_I2C_COMM1)
  sendstop
  
' Write COMM2 + first digit address
  sendstart
  writeByte(TM1637_I2C_COMM2)
  
' Write the data bytes
  For k=0 To 3
    writeByte(segments(k))
  Next k
  sendstop
  
' Write COMM3 + brightness
  sendstart
  writeByte(TM1637_I2C_COMM3 + (m_brightness And &H0f))
  sendstop
End Sub
'=============================================
Sub sendstart
  SetPin m_pinDIO, DOUT
'  bitDelay
  Pause 0.01
End Sub
'=============================================
Sub sendstop
  SetPin m_pinDIO, dout
  SetPin m_pinClk, DIN
  SetPin m_pinDIO, DIN
'  bitDelay
  Pause 0.01
End Sub
'=============================================
Sub writeByte(b As integer) As integer
  Local integer i,ack,odata = b
' 8 Data Bits
  For i=0 To 7
' CLK low
    SetPin m_pinClk,dout
' Set data bit
    If (odata And 1) Then
      SetPin m_pinDIO,DIN
    Else
      SetPin m_pinDIO,DOUT
    EndIf
'Pause 0.01
' CLK high
    SetPin m_pinClk, DIN
    odata = odata >> 1
  Next i
'Pause 0.01
' Wait for acknowledge
' CLK to zero
  SetPin m_pinClk, dout
  SetPin m_pinDIO, DIN
' CLK to high
  SetPin m_pinClk, din
  ack = Pin(m_pinDIO)
  If (ack = 0) Then
    SetPin m_pinDIO, dout
  EndIf
  SetPin m_pinClk, dout
  Pause 0.01
End Sub
'=============================================
Function encodeDigit(digit As integer) As integer
  encodeDigit=digitToSegment%(digit And &H0f)
End Function
'=============================================
Sub convertnumber(dd() As integer,n As integer, nolead As integer)
  Local integer d(2),m
  m=Abs(n Mod 10000)
  PRESS ANY KEY ...                   If n<0 Then m=Abs(n Mod 1000)
  d(0)=(m - (m Mod 1000))
  d(1)=(m - d(0) - (m Mod 100))
  d(2)=(m - d(0) - d(1) - (m Mod 10))
  dd(3)=encodeDigit(m - d(0) -d(1)- d(2))
  dd(0)=encodeDigit(d(0)\1000)
  dd(1)=encodeDigit(d(1)\100)
  dd(2)=encodeDigit(d(2)\10)
  If nolead Then
    If d(0)=0 Then
      dd(0)=0
      If d(1)=0 Then
        dd(1)=0
        If d(2)=0 Then
          dd(2)=0
        EndIf
      EndIf
    EndIf
    If n<0 Then
      If dd(2)=0 Then
        dd(2)=64
      Else
        If (dd(1)=0) Then
          dd(1)=64
        Else
          dd(0)=64
        EndIf
      EndIf
    EndIf
  Else
    If n<0 Then dd(0)= 64
  EndIf
End Sub
'=============================================
Sub converttime(dd() As integer,displaycolon As integer,nolead As integer) As i
  nteger
  Local integer i=Val(Left$(Time$,2))*100+Val(Mid$(Time$,4,2))
  convertnumber(dd(),i,nolead)
  If displaycolon Then dd(1)=dd(1) Or &H80
End Sub
'=====[ MAIN CODE ]============================================================
  
  TM1637Init(CLK,DIO)' initialise the display
  setbrightness(15)' load the brightness into the global variable
  setsegments(displaydata()) 'displaydata is set to zeroes so clear the display
  PRESS ANY KEY ...
  mytime$=Time$
  Pause 1000
  
  Do
    If mytime$<>Time$ Then 'the clock seconds have changed
      If Val(Right$(Time$,1)) Mod 2 Then 'flash the colon each second
        converttime(displaydata(),colon,noleadingzeros) 'set the time into the di
        splay array including the colon but no leading zeroes
      Else
        converttime(displaydata(),nocolon,noleadingzeros)'set the time into the d
        isplay array without the colon or leading zeroes
      EndIf
      setsegments(displaydata()) 'update the display
      mytime$=Time$
    EndIf
    Pause 500
  Loop
  
'==============================================================================