Bascom mit I2C Speicher

Declare Sub Write_eeprom(byval Adresh As Byte , Byval Adresl As Byte ,
Byval Value As Byte)
Declare Sub Read_eeprom(byval Adresh As Byte , Byval Adresl As Byte ,
Value As Byte)

' Adresse erzeugen:
' Pin A0 und A1 sind intern mit Pulldowns versehen, sind also
' wenn extern nicht beschaltet 0
' Die Der Baustein halt serienmäßig die Adresse Binär:
' 1 0 1 0 0 A1 A0 R/W
' also, angenommen man möcht bei A0 = 0 und A1=0 schreiben:
' Adresse: 10100000 = 160
' Lesen Adresse: 10100001 = 161
'
' der 24c128 und 24c256 brauchen für die Adressierung 2 Byte
' Den High-Byte der Adresse und den Lowbyte der Adresse.
' Einfach, da die soviel Speicher habn :o)

Const Addressw = 160                                        'slave
write address
Const Addressr = 161                                        'slave
read address

Dim B1 As Byte
Dim Value As Byte                                           'dim byte
Dim Adresh As Byte                                          'Highbyte
der Adresse
Dim Adresl As Byte                                          'Lowbyte
der Adresse
Dim A As Byte
'allgemeine Variable für Berechnungen

For A = 1 To 5                                              ' die
ersten 5 Byte schreiben
   Value = A + 100                                          'Beginnend
mit Zahlenwert 105 um Verwechslungen zu vermeiden
   Call Write_eeprom(1 , A , Value)                         'Daten
schreiben
Next A

For A = 1 To 5                                              'die
geschriebenen 5 Byte auslesen
   Call Read_eeprom(1 , A , Value)                          'auslesen
   Print Value                                              'Ausgabe
an UART
Next A


'sample of writing a byte to EEPROM AT2404
Sub Write_eeprom(byval Adresh As Byte , Adresl As Byte , Value As
Byte)
    I2cstart                                                'start
condition
    I2cwbyte Addressw                                       'slave
address
    I2cwbyte Adresh                                         'asdress H
of EEPROM
    I2cwbyte Adresl                                         'asdress L
of EEPROM
    I2cwbyte Value                                          'value to
write
    I2cstop                                                 'stop
condition
    Waitms 10                                               'wait for
10 milliseconds
End Sub


'sample of reading a byte from EEPROM AT2404
Sub Read_eeprom(byval Adresh As Byte , Adresl As Byte , Value As Byte)
   I2cstart                                                 'generate
start
   I2cwbyte Addressw                                        'slave
adsress
   I2cwbyte Adresh                                          'asdress H
of EEPROM
   I2cwbyte Adresl                                          'asdress L
of EEPROM
   I2cstart                                                 'repeated
start
   I2cwbyte Addressr                                        'slave
address (read)
   I2crbyte Value , Nack                                    'read
byte
   I2cstop                                                  'generate
stop
End Sub


' when you want to control a chip with a larger memory like the 24c64
it requires an additional byte
' to be sent (consult the datasheet):
' Wires from the I2C address that are not connected will default to 0
in most cases!

'   I2cstart                                                'start
condition
'   I2cwbyte &B1010_0000                                    'slave
address
'   I2cwbyte H                                              'high
address
'   I2cwbyte L                                              'low
address
'   I2cwbyte Value                                          'value to
write
'   I2cstop                                                 'stop
condition
'   Waitms 10