' **********************************************************************
' ** Program name: PPI.BAS   -   Version :   1.1   -   22 May 2000    **
' ** Compiler :    BASCOM 8051, (IDE V.1.0.0.20, LIB V.1.20)          **
' ** Board : K51-AVR and GPC F2                                       **
' ** Firm:   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:  Adriano Pedrielli                                   **
' **********************************************************************
'
' This program shows, in hexadecimal format, the status of the eight lines
' connected to IC1 (PCF8574A or 8574P, see constants declaration, through
' two TTL lines driven by the family 51 microcontroller-based GPC F2
' board.
'
' This program is controlled through the RS 232 serial line so it is essential
' to connect a free COM port on the PC to the connector CN3 of GPC(r) F2.
' Configure the BASCOM 8051 terminal using menu Option/Communication, select
' the COM port and set baud rate to 9600, parity to none, databits to 8 and
' stopbits to 1.
'
' Perform the following connections :
' GPC F2                    K51 AVR
' +5Vdc   (pin15 CN3) ----> +5Vdc (pin1 CN6)
' Gnd     (pin16 CN3) ----> Gnd   (pin2 CN6)
' T0 P3.4 (pin3 CN3)  ----> SD    (pin7 CN6)
' T1 P3.5 (pin1 CN3)  ----> SC    (pin8 CN6)
'
' Before compiling set in menu Option/Compiler/Misc/ :
' Byte End 5F
'
'***********************************************************************
'
'********************** Compiler directives ****************************
'
$regfile = "REG51.DAT"                         ' list of CPU registers
$romstart = &H8050                             ' code start address
                                          ' &H8050 for MO52 Rel.1.1 in RAM IC8
                                          ' &H0000 for EPROM withput RAM IC8

$ramstart = &HD000                             ' add. of variables external RAM
$ramsize = &H2800                              ' assign 10K of external RAM
                                               ' to variables
$crystal = 11059200                            ' CPU clock frequence
$baud = 9600                                   ' RS-232 communication speed
$large                                         ' 16 bit addressing
'
' ******************************* 8xc51 PIN list ***********************
'
Config Sda = P3.4                              ' line P3.4 or T0 (pin 3 of CN3)
                                               ' on GPC(r) F2 is Data signal.
Config Scl = P3.5                              ' line P3.5 or T1 (pin 1 of CN3)
                                               ' on GPC(r) F2 is Clock signal.
Buz Alias P1.2                                 ' Pin 3 of GPC F2 microcontroller
                                               ' is connected to the on board
                                               ' buzzer.

Const Cler = 12                                ' clear screen code
Const Bel = 7                                  ' Bell code
'
'********************* Constants declaration ***************************
'
Dim Saa1064 As Const &H38                      ' Slave address SAA1064
Dim Wsaa1064 As Const &H70                     ' Slave address SAA1064 in Write
Dim Rsaa1064 As Const &H71                     ' Slave address SAA1064 in Read
'****************** Addresses list for Saa1064 *************************
Dim Ctb As Const 0                             ' Ind. Control byte
Dim Dig1 As Const 1                            ' Ind. Digit 1
Dim Dig2 As Const 2                            ' Ind. Digit 2
Dim Dig3 As Const 3                            ' Ind. Digit 3
Dim Dig4 As Const 4                            ' Ind. Digit 4
' **********************************************************************
' Comment the declaration of the component not used, uncomment the other
' declaration
'
Dim Pcf8574 As Const &H3C                      ' Slave address PCF8574A
Dim Wpcf8574 As Const &H78                     ' Slave address PCF8574A in Write
Dim Rpcf8574 As Const &H79                     ' Slave address PCF8574A in Read

'Dim Pcf8574 As Const &H24                 ' Slave address PCF8574P
'Dim Wpcf8574 As Const &H48                ' Slave address PCF8574P in Write
'Dim Rpcf8574 As Const &H49                ' Slave address PCF8574P in Read
'
'*********************** Variables declaration *************************
'
Dim Dig As Byte                                ' value of a digit
Dim Cifh As Byte                               ' 4 bit high in HEX for figure
Dim Cifl As Byte                               ' 4 bit low in HEX for figure
Dim N1 As Byte                                 ' number 1 byte for DY3 and DY4
Dim Valore As Byte                             ' number to convert
Dim T As Byte                                  ' code of key pressed
Dim Tstr As String * 1                         ' string of one character
'
'********************* Procedures declaration **************************
'
Declare Sub Iniz                               ' Peripherals initialization
Declare Sub Cifre (valore As Byte , Cifh As Byte , Cifl As Byte )
                                          ' converts a number in 2 HEX figures
Declare Sub Digit (dig As Byte )               ' Converts a number in range
                                               ' 0-F in 7 segments
Declare Sub Vis_num (n1 As Byte)               ' Shows a byte in HEX
'
'*************************** Main program ******************************
'
Main:                                          ' Delay for signals settling
Waitms 1
   Call Iniz                                   ' initializations
Do
   Do
      I2creceive Rpcf8574 , N1                 ' read the status of
                                               ' PCF8574A 8 inputs
      Call Vis_num(n1)                         ' Show the byte in HEX
      T = Inkey                                ' read a char from serial port
   Loop Until T <> 0                           ' exit if received a character
   If T = 27 Then                              ' ESC key has been pressed
      Exit Do                                  ' exit from loop
   Else
      Print Chr(bel);                          ' key non valid
   End If
Loop
   Ljmp 0                                      ' exit and restart monitor
End
'
'*************************** Programma end ******************************
'
'
'**************************** Procedures ********************************
'
' ********************** Peripherals initialization ********************
' This procedure performs all the system initializations.
' Parameters:
' Input : nothing
' Output : nothing
' ************************************************************************
'
Sub Iniz                                       ' Peripherals initialization
   Print Chr(cler);                            ' clear screen
   Print "Demo K51-AVR 8 input on IC1(PCF8574A or 8574P) through GPC F2";
   Print " rel.1.1 22/05/2000"
   Print
   Print "Press ESC to exit"
   Do
      I2creceive Rsaa1064 , Valore             ' Read the 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 48                                 ' set DY1 "I"
   I2cwbyte 84                                 ' set DY2 "n"
   I2cwbyte 0                                  ' set DY3 off
   I2cwbyte 0                                  ' set DY4 off
   I2cstop
End Sub
'
' *********** 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 from 0 to F
' Output : dig as byte, value in 7 segments format.
' ************************************************************************
'
Sub Digit (dig As Byte )                       ' Converts a number in
                                               ' range 0-F in 7 segments
   If Dig < 16 Then                            ' number is lower than 16
      Dig = Lookup(dig , Tab_7seg)             ' read value in table
   Else
      Dig = 0                                  ' if = 16 or greater reset
   End If
End Sub
'
' ***************** Converts 1 byte in two HEX figures ********************
' 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 , Cifh As Byte , Cifl 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 **********************
' This procedure allows to show a byte in hexadecimal format.
' E.g.: 255= FFH, 32= 20H etc.
' Parameters:
' Input : N1 as byte, figure to show in HEX format
' Output : output
' ************************************************************************
'
Sub Vis_num (n1 As Byte)                       ' visualizes a byte in HEX
      I2cstart                                 ' Start sequence for I2CBUS
      I2cwbyte Wsaa1064                        ' slave address
      I2cwbyte Dig3                            ' point to display 3 (DY3)

      Call Cifre(n1 , Cifh , Cifl)             ' convert number in 2 HEX figures
      Call Digit(cifh)                         ' convert decines in 7 segments
      I2cwbyte Dig                             ' output to display DY3

      Call Digit(cifl)                         ' convert units in 7 segments
      I2cwbyte Dig                             ' 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
' **********************************************************************
'