'------------------- AN 4 -----------------------------
'          Copyright 1998 MCS Electronics
'                   CLOCK.BAS
'This AN shows how to use the PCF8583 I2C clock device
'The PCF8583 is a PHILIPS device. Look at the datasheet for more details
'I used a prototype board from dontronics with the hardware
'simulator to test the program
'------------------------------------------------------
'declare used subs
Declare Sub Settime(s As Byte , M As Byte , H As Byte , D As Byte , Month As Byte)
Declare Sub Gettime


'declare vairables
Dim S As Byte , M As Byte , H As Byte , D As Byte , Month As Byte
Dim Wm As Byte , Yd As Byte

Call Settime(0 , 0 , 0 , 29 , 11)       'set time

Do
   Call Gettime                         'get time
Loop
End



Sub Gettime
    Dim Dum As Byte
    I2cstart                            'generate start
    I2cwbyte &HA0                       'write addres of PCF8583
    I2cwbyte 2                          'select second register
    I2cstart                            'generate repeated start
    I2cwbyte &HA1                       'write address for reading info
    I2crbyte S , Ack                    'read seconds
    I2crbyte M , Ack                    'read minuts
    I2crbyte H , Ack                    'read hours
    I2crbyte Yd , Ack                   'read year and days
    I2crbyte Wm , Nack                  'read weekday and month
    I2cstop                             'generate stop

    Print "Time " ; Bcd(h) ; ":" ; Bcd(m) ; ":" ; Bcd(s)
    Print "Day : " ; Bcd(yd) ; " Month : " ; Bcd(wm)
  Lcd "Time " ; Bcd(h) ; ":" ; Bcd(m) ; ":" ; Bcd(s)
  Lcd "Day : " ; Bcd(yd) ; " Month : " ; Bcd(wm)

Rem You Could Also Use The Lcd Statement For Displaying The
Rem Time On The Lcd Display
End Sub


Sub Settime(s As Byte , M As Byte , H As Byte , D As Byte , Month As Byte)
    'values are stored as BCD values so convert the values first
    S = Makebcd(s)                      'seconds
    M = Makebcd(m)                      'minuts
    H = Makebcd(h)                      'hours
    D = Makebcd(d)                      'days
    Month = Makebcd(month)              'months

    I2cstart                            'generate start
    I2cwbyte &HA0                       'write address
    I2cwbyte 0                          'select control register
    I2cwbyte 8                          'set year and day bit for masking
    I2cstop                             'generate stop


    I2cstart                            'generate start
    I2cwbyte &HA0                       'write mode
    I2cwbyte 2                          'select seconds Register
    I2cwbyte S                          'write seconds
    I2cwbyte M                          'write minuts
    I2cwbyte H                          'write hours
    I2cwbyte D                          'write days
    I2cwbyte Month                      'write months
    I2cstop
End Sub