' **********************************************************************
' ** Program: k51ad4e.BAS    -    Version : 1.1   -   27 January 2004 **
' ** Compiler : Bascom AVR IDE - LIB 1.11.7.4                         **
' ** Scheda : K51-AVR driven by GMB HR84 and GMM AM08                 **
' ** Society: grifo(r) ITALIAN TECHNOLOGY                             **
' ** Via Dell' Artigiano 8/6          40016 San Giorgio di Piano (BO) **
' ** Tel.+39 051 892 052     Fax +39 051 893 661                      **
' ** http://www.grifo.com    http://www.grifo.it                      **
' ** sales@grifo.it          tech@grifo.it          grifo@grifo.it    **
' **                                                                  **
' ** Written by:  Graziano Gaiba                                      **
' **********************************************************************
'
'
' This demo allows to drive an I2C BUS peripheral on board of K51-AVR, PCF8591,
' through mini-BLOCK module GMB HR84 and grifo(r) mini module.
' PCF 8591 is provided with four analog inputs for A/D conversions with 8 bits
' resolution, all the operations of conversion and combination acquisition are
' performed through synchronous serial interface I2C BUS.
' This demo allows to set which channel to convert through PC keyboard, and to
' read the combination on the 7 segments display of K51-AVR.
'
'
' 27.01.04 - Rel 1.1 By Graziano Gaiba per GMM AM08
'
'   Compiled file is smaller than 2048 bytes, so it can becompliled with free
'   demo of BASCOM AVR.
'
'
' !!!!!!!!!!!!!!!!!!!!!!!!!!! IMPORTANT !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
' In menu Options | Compiler | Chip, set:
'
' Chip:       M8
' HW Stack:   at least 64
' Soft Stack: at least 32
' Framesize:  at least 64
'
'
'***********************************************************************
'****************** Compiler directives **************************
'
$regfile = "m8def.dat"
$crystal = 7372800
$baud = 19200

Config Sda = Portc.4                                        ' I2C serial DATA
Config Scl = Portc.5                                        ' I2C serial CLK
'
'********************* Constants declaration ***************************
'
Const Saa1064 = &H38                                       ' Slave address SAA1064
Const Wsaa1064 = &H70                                       ' Slave address SAA1064 in Write
Const Rsaa1064 = &H71                                       ' Slave address SAA1064 in Read
'****************** Addresses list for Saa1064 *************************
Const Ctb = 0                                               ' Address Control byte
Const Dig1 = 1                                              ' Address Digit 1
Const Dig2 = 2                                              ' Address Digit 2
Const Dig3 = 3                                              ' Address Digit 3
Const Dig4 = 4                                              ' Address Digit 4
'***********************************************************************
'
Const Pcf8591 = &H48                                        ' Slave address PCF8591
Const Wpcf8591 = &H90                                       ' Slave address PCF8591 in Write
Const Rpcf8591 = &H91                                       ' Slave address PCF8591 in Read
'
'*********************** Variables declaration *************************
'
' Usated for I2C bus communication
Dim Dato As Byte                                            ' Combination read
Dim C As Byte                                               ' Channel to convert

' Number to send to 7-segments display
Dim Cifh As Byte                                            ' Most significant nibble
Dim Cifl As Byte                                            ' Least significant nibble
'
'********************* Procedures declaration **************************
'
Declare Sub Iniz()                                          ' Peripherals initialization
Declare Function Ad(byval Ch As Byte ) As Byte              ' A/D converter management
Declare Sub Canale()                                        ' Channel number management
Declare Sub Cifre(byval Valore As Byte )
                                          ' converts a number in 2 HEX figures
Declare Function Digit(byval Dig As Byte ) As Byte          ' Converts a number in range
                                               ' 0-F in 7 segments
Declare Sub Vis_num(byval n1 As Byte)                             ' Shows a byte in HEX
'
'*************************** Main program ******************************
'
Main:
   Print "Demo PCF8591 (4 A/D channels)"

   Call Iniz()                                                ' initializations
   C = 0
   Print
   Print "Press + to increment the channel to convert"
   Print "Press - to increment the channel to convert"
   Print
   Do
      Dato = Ad(c )                                         ' Perform acquisition
      Call Vis_num(dato )                                   ' Show byte in HEX
      Call Canale()
   Loop
Return
End
'
'**************************** Program end ******************************
'
'
'**************************** Procedures *******************************
'
'
' Channel number management
'
Sub Canale()

  Local Valore As Byte

   Valore = Inkey()
   If Valore = "+" Then
      If C = 3 Then
         C = 0
      Else
         Incr C
      End If
   End If
   If Valore = "-" Then
      If C = 0 Then
         C = 3
      Else
         Decr C
      End If
   End If
End Sub
'
'
' ********************** Peripherals initialization ********************
' This procedure performs all the system initializations.
' Parameters:
' Input : nothing
' Output : nothing
' **********************************************************************
'
Sub Iniz()                                                  ' Inizializzazione periferiche

  Local Valore As Byte

   Do
      I2creceive Rsaa1064 , Valore                          ' read status register
   Loop Until Valore = 0                                    ' wait for SAA1064 to turn on
   I2cstart                                                 ' Start sequence for I2CBUS
   I2cwbyte Wsaa1064                                        ' Communicate the Slave address
   I2cwbyte Ctb                                             ' point to control register
   I2cwbyte &B00100111                                      ' bit0 =1 dynamic mode
                                          ' bit1 =1 digit 1+3 not blanked
                                          ' bit2 =1 digit 2+4 not blanked
                                          ' bit3 =0 no test segment
                                          ' bit4 =0 no 3mA segment current
                                          ' bit5 =1 6mA segment current
                                          ' bit6 =0 no 12mA segment current
                                          ' bit7 =0 indifferent
   I2cwbyte 0                                               ' set DY1 off
   I2cwbyte 0                                               ' set DY2 off
   I2cwbyte 0                                               ' set DY3 off
   I2cwbyte 0                                               ' set DY4 off
   I2cstop
End Sub
'
'
' ******************** A/D converter management ************************
' This procedure allows to perform an analogic conversion through one of
' the four channels available on IC2 (PCF8591).
' Parameters:
' Input : C as byte, indicates the channel to convert (0...3)
' Output : byte, value in the range from 0 to 255 (0v...+Vref)
' **********************************************************************
'
Function Ad(byval Ch As Byte) As Byte                       ' A/D converter management

  Local Valore As Byte

   Ch = Ch And &H03                                         ' keep Bit 0 and Bit 1
   I2csend Wpcf8591 , Ch                                    ' point to the channel to convert
   I2creceive Rpcf8591 , Valore                             ' read previous conversion
   I2creceive Rpcf8591 , Valore                             ' read current conversion

   Ad = Valore

End Function
'
'
' ******** Converts a figure in range from 0 to F in 7 segments ********
' This procedure converts a figure in range from 0 to F in 7 segments
' format, if value is greater than F the display is off.
' Parameters:
' Input : dig as byte, value in the range from 0 to F
' Outout : byte, value in 7 segments format.
' **********************************************************************
'
Function Digit(byval Dig As Byte ) As Byte                  ' Converts a number in range

  Local Valore As Byte
                                               ' 0-F in 7 segments
   If Dig < 16 Then                                         ' if number is lower than 16
      Valore = Lookup(dig , Tab_7seg)                       ' read value from table
   Else
      Valore = 0                                            ' if = 16 or greater reset
   End If

   Digit = Valore

End Function
'
'
' ***************** Converte 1 byte in due cifre HEX ********************
' This procedure converts 1 byte in range from 0 to 255 in two 4 bits
' hexadecimal figures.
' Parameters:
' Input : Valore as byte, value in the range from 0 to 255
' Output :  Cifh as byte, figure of high nibble
'           Cifl as byte, figure of low nibble
' ************************************************************************
'
Sub Cifre(valore As Byte)
                                          ' converts a number in two HEX figures
   Cifh = Valore And &HF0                                   ' mask 4 high bits
   Cifh = Cifh / 16                                         ' shift to low the 4 high bits
   Cifl = Valore And &H0F                                   ' mask the 4 low bits
End Sub
'
'
' *********************** Visualizes a byte in HEX *********************
' The first display visualizes the number of the channel being
' converted, the second display is off.
' This procedure allows to show a byte in hexadecimal format
' in the two displays on the right. E.g.: 255= FFH, 32= 20H etc.
' Parameters:
' Input : N1 as byte, number to visualize in HEX
' Output : nothing
' **********************************************************************
'
Sub Vis_num(n1 As Byte)                                     ' visualizes a byte in HEX

  Local Valore As Byte

   I2cstart                                              ' Start sequence for I2CBUS
   I2cwbyte Wsaa1064                                     ' slave address
   I2cwbyte Dig1                                         ' point to display 1 (DY1)
   Valore = Digit(c)                                        ' convert the decines figure
                                            ' in 7 segments
   I2cwbyte Valore                                          ' output to first display DY1
   I2cwbyte 0                                            ' output to second display DY2

   Call Cifre(n1)                                           ' convert  number in 2 HEX figure
   Valore = Digit(cifh)                                     ' convert figure in HEX
                                            ' in 7 segments
   I2cwbyte Valore                                          ' output to display DY3

   Valore = Digit(cifl)                                     ' convert figure in HEX
                                            ' in 7 segments
   I2cwbyte Valore                                          ' output to display DY4

   I2cstop                                               ' Stop sequence for I2CBUS
End Sub
'
' ** Conversion table for 7 segments figure in the range from 0 to 15 **
Tab_7seg:
' num.  0      1      2      3      4      5      6      7      8      9
Data &H3F , &H06 , &H5B , &H4F , &H66 , &H6D , &H7D , &H07 , &H7F , &H6F
' num.  A      b      C      d      E      F
Data &H77 , &H7C , &H39 , &H5E , &H79 , &H71
' **********************************************************************
'