' **********************************************************************
' ** Program: DEMO_PPI.BAS   -    Version : 1.1   -   29 January 1999 **
' ** Compiler: BASCOM LT (IDE V.1.20, LIB V.1.27)                     **
' ** Card: GPC(r) 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    **
' **                                                                  **
' ** Developed by:  Adriano Pedrielli                                 **
' **********************************************************************
'
' This program manages the 24 TTL digital I/O lines driven by PPI 82c55
' peripheral device and it drives the on board buzzer to genrate sound
' feed back during output setting.
' To visualize the lines status it is necessary to connect the CN2 of
' GPC(r) F2 to CN1 connector of TIO 16 or CN15 of DEB 01, through a 20
' ways flat cable.
'
'***********************************************************************
'
'********************** Compiler directive ******************************
'
$romstart = &H8050                     ' Code area start address
$ramstart = &HD000                     ' Data area start address
$ramsize = &H2800                      ' Data area size = 10K
$crystal = 11059200                    ' Microcontroller clock frequency
$baud = 9600                           ' RS 232communication speed
$large                                 ' 16 bits addressing mode
'
'******************** Constant declaration *****************************
'
Dim Cnt As Const &HFA03                ' Control and command register of 82c55
Dim Pda As Const &HFA00                ' Port A data register
Dim Pdb As Const &HFA01                ' Port B data register
Dim Pdc As Const &HFA02                ' Port C data register
Buzzer Alias P1.2                      ' Microprocessor pin rename
'
'******************** Procedure declaration ****************************
'
Declare Sub Vis_byte(v8bit As Byte)     ' Shows each bit of a byte
Declare Sub Show_dip1                ' Acquire DIP1 dip switch
'
'******************** Variable declaration *****************************
'
Dim V8bit As Byte                       ' 8 bits variable for Vis_byte procedure
Dim V1bit As Bit                        ' 1 bit  variable for generic use
Dim X As Byte , X1 As Byte              ' 8 bits variable for generic use
Dim X8bit As Byte , D8bit As Byte       ' 8 bits variable for generic use
'
'************************* Main program ********************************
'
Main:
Waitms 1                                ' Delay for signals adjustement
Out Cnt , 130                           ' Sets mode 0; port A and port C in output;
                                        ' port B in input because connected to DIP1
Out Pda , 255                           ' Sets 8 lines of port A to 1 level
Out Pdc , 255                           ' Sets 8 lines of port C to 1 level
Print
Print "  Demo program for PPI 82c55 peripheral device. V. 1.1 for GPC(r) F2"
Print
Print "The program sequentially enables one digital outputs on port A and port C,"
Print "at the same time it shows the status of port B that is connected to DIP1."
Print "Each activation of the two ports, is annouced by an acoustics tone"
Print
Print
Print "        DIP1 dip switch"
Print
Print "  1   2   3   4   5   6   7   8"
Do
   D8bit = 1                            ' Sets first bit to enable
   For X1 = 1 To 8                      ' Loops 8 times
      X8bit = Not D8bit                 ' Toggles all bits of variable
      Out Pda , X8bit                   ' Sets port A output lines
      Rotate D8bit , Left               ' Shifts left one bit
      Show_dip1                         ' Shows the DIP1 status and generates sound
   Next X1                              ' End loop
   Out Pda , 255                        ' Sets 8 lines of port A to 1 level
   D8bit = 1                            ' Sets first bit to enable
   For X1 = 1 To 8                      ' Loops 8 times
      X8bit = Not D8bit                 ' Toggles all bits of variable
      Out Pdc , X8bit                   ' Sets port C output lines
      Rotate D8bit , Left               ' Shifts left one bit
      Show_dip1                         ' Shows the DIP1 status and generates sound
   Next X1                              ' End loop
   Out Pdc , 255                        ' Sets 8 lines of port A to 1 level
Loop                                    ' Endless loop
End
'
'************************ Main program end *****************************
'

'
'*************************** Procedure *********************************
'
' Procedure that shows the DIP1 dip switch status
' Input parameter:  none
' Output parameter: none
Sub Show_dip1
   V8bit = Inp(pdb )                    ' Acquires port B value
   Vis_byte (v8bit)                     ' Shows all the 8 bit status
   Print Chr(13);                       ' Places cursor at the begin of the row
   Waitms 255                           ' Delays 255 ms
   Sound Buzzer , 200 , 100             ' Generates a 2 KHz frequency signal for 100ms
   Buzzer = 1                           ' Sets to 1 the buzzer line
End Sub
'
' Procedure that shows each bit status of a byte
' Input parameter:  v8bit = byte = value to be displayed as bit status
' Output parameter: none
Sub Vis_byte (v8bit As Byte )
For X = 1 To 8                          ' Shows 8 times the current bit
  V1bit = V8bit And &H01                ' Masks bit 0
  If V1bit = 0 Then                     ' Tests current bit status
                  Print " On " ;        ' If status=0 shows On
               Else
                  Print " Off" ;        ' If status=1 shows Off
               End If
  Rotate V8bit , Right                  ' Shift right one bit
Next X
End Sub