' example:
T$="The BackShed eeprom test "

eeWrite$ 70, t$

Print eeRead$(70,Len(t$))+"<"
Print eeGet$(70)+"<"

end



'******************************
Sub eeWrite$ (address, text$)
' Writes a string to AT24C32
'******************************

I2CADDR=&H57 ' 24C32-DS3231
a=0

If Len(text$)+address>4095 Then Print "Error: Address to high!":End

I2C open 100,100 'ENABLE I2C
For x= address To address+Len(text$) 'writes 0-byte at the end!
a=a+1
msb=Int(x/256) 'MSB
lsb=x Mod 256 'LSB

I2C write I2CADDR, 0, 3, msb, lsb, Asc(Mid$(text$,a,1))

If MM.I2C <>0 Then Print "Error! 1=NAK 2=TIMEOUT"; MM.I2C: End Sub
Pause 5
Next x
I2C close

Print "At"address" string "+Chr$(34)+text$+Chr$(34)+"is written into EEPROM."
End Sub


'******************************
Function eeRead$ (address, bytes)
' Reads a string from AT24C32
'******************************

I2CADDR=&H57 ' 24C32-DS3231
eeRead$=""

If address>4095 Then Print "Error: Address to high!":End
If bytes>255 Then Print "Error: String too long!":End

I2C open 100,100 'ENABLE I2C
For x= address To address+bytes-1

msb=Int(x/256) 'MSB
lsb=x Mod 256 'LSB

I2C write I2CADDR, 0,2,msb,lsb
I2C read I2CADDR, 0,1,tmp

If MM.I2C <>0 Then Print "Error! 1=NAK 2=TIMEOUT"; MM.I2C: End Sub
eeRead$=eeRead$+Chr$(tmp)

Next x
I2C close
End Function


'******************************
Function eeGet$ (address)
' Gets a zero-terminated string from AT24C32
'******************************

I2CADDR=&H57 ' 24C32-DS3231
eeGet$=""

If address>4095 Then Print "Error: Address to high!":End

I2C open 100,100 'ENABLE I2C

Do

msb=Int(address/256) 'MSB
lsb=address Mod 256 'LSB

I2C write I2CADDR, 0,2,msb,lsb
I2C read I2CADDR, 0,1,tmp

If MM.I2C <>0 Then Print "Error! 1=NAK 2=TIMEOUT"; MM.I2C: End Sub
If tmp=0 Then Exit 'leave loop
eeGet$=eeGet$+Chr$(tmp)
address=address+1

Loop While Len(eeGet$)<255
I2C close
End Function

'**************************************
' ERASE WHOLE EEPROM (fill with zero)
' using PAGE WRITE
'**************************************
Sub eeErase
Dim fill(34) ' fill will contain 2 bytes for address + 32 fillbytes
I2CADDR=&H57 ' 24C32-DS3231
K=&H00 'zero value or some fill value

For i = 2 To 34:fill(i)=K: Next i

Print "Erasing ..."
I2C open 100,100 'ENABLE I2C
For J=&h0 To &hF 'MSB
For I=&h0 To &hFF Step 32'LSB
fill(0)=j:fill(1)=i
'fill(0)+(1) = MSB + LSB
I2C write I2CADDR, 0,34,fill(0)

Pause 5 '? Write needs some time ...
If MM.I2C <>0 Then Print "1=NAK 2=TIMEOUT"; MM.I2C,j,i:End:EndIf
Next i
L=(j*256+I)
Print "Byte ";L, " ";Chr$(13);
Next j
I2C close
Print "EEPROM HAS BEEN ERASED "

End Sub

'********************************************
'********************************************
' for ATMEL 24V32 (32kBit EEPROM) on DS3231
' MMBasic 4.5 for Maximite/Duinomite
'********************************************
'********************************************
'
' eeWrite$: writes a string to address
' eeRead$: some bytes from address
' eeGet$: reads a string from address
' eeWriteN: writes a number (1 byte) to address
' eeReadN: reads a number (1 byte) from address
' address may be between 0 to 4095
'
' eeSaveF: writes a 32 bit floatinpoint number
' eeLoadF: reads a 32 bit floatinpoint number
' to/back from EEPROM using PEEK and POKE
' uses eeWriteN respectively eeReadN
'
' eeErase: deletes the whole eeprom
' eeDump: shows content of eeprom
'
'
' EEPROM-Collection v0.5
' by twofingers 08-2014
' with parts from MMBasic Library
' (should be public domain)
'
'********************************************
'********************************************

' example code:

Dim Z(20)

'debug = 1 ' debugmode switch

test = Pi
Print "Save: "test
eeSaveF (0, test)
test=0
Print "Set to zero:"test
eeLoadF (0, test)
Print "Restored: "test
Print:Print

' test an array
For i = 1 To 20
Z(i)=1/i
Print "Save: ",i, Z(i)
eeSaveF (i*4, z(i))
z(i)=0
Print "Set to zero:",i, Z(i)
eeLoadF (i*4, z(i))
Print "Restored: ",i, Z(i)
Print
wait "<Press any key>"
Next i
eeDump

End
'********** END EXAMPLE CODE ************
'****************************************

'******************************
Sub eeSaveF (address, v)
' Saves a floatingp. var to AT24C32
'******************************
local i

For i = 0 To 3
eewriteN address+i, Peek(VAR v,i)
Next i

End Sub


'******************************
Sub eeLoadF (address, v)
' Load a floatingp. var from AT24C32
'******************************
local i

For i = 0 To 3
Poke VAR v,i, eeReadN(address+i)
Next i

End Sub



'******************************
Sub eeWriteN (address, Number)
' Write a number to AT24C32
'******************************
local MSB, LSB
I2CADDR=&H57 ' 24C32-DS3231

I2C open 100,100 'ENABLE I2C
msb=Int(address/256) 'MSB
lsb=address Mod 256 'LSB

I2C write I2CADDR, 0, 3, msb, lsb, Number
Pause 5
If MM.I2C <>0 Then Print "Error! 1=NAK 2=TIMEOUT"; MM.I2C:End:EndIf
I2C close

If debug Then Print Number;" written into EEPROM."
End Sub


'******************************
Function eeReadN (address)
' Read a number from AT24C32
'******************************
local MSB, LSB
I2CADDR=&H57 ' 24C32-DS3231

I2C open 100,100 'ENABLE I2C
msb=Int(address/256) 'MSB
lsb=address Mod 256 'LSB

I2C write I2CADDR, 0,2,msb,lsb
I2C read I2CADDR, 0,1,eeReadN

If MM.I2C <>0 Then Print "ERROR! 1=NAK 2=TIMEOUT"; MM.I2C:eeReadN=-1:End:EndIf
I2C close

End Function


'**************************************
' EEPROM komplett LESEN
' Shows content from AT24C32
'**************************************
Sub eedump

Local i, j, y, L, RTCBUFF(4096)
I2CADDR=&H57 ' 24C32-DS3231

For I = 0 To 4095
RTCBUFF(I)=&H0
Next I

Print " Reading buffer in ..."

I2C open 100,100 'ENABLE I2C
For J=&H0 To &HF
For I=&h0 To &hFF
L=(j*256+I)

I2C write I2CADDR, 0,2,J,I
I2C read I2CADDR, 0,1,RTCBUFF(L)

If MM.I2C <>0 Then Print "ERROR! 1=NAK 2=TIMEOUT"; MM.I2C,j,i:End:EndIf
Next I
Next J

I2C close

Print " Show buffer (Press any key!) ..."

For I=0 To 4095 Step 16
Print "Byte ";Format$(I,"%4g");" ||";
For y = 0 To 15
Print Right$("0"+Hex$(RTCBUFF(I+y)),2);"|";
Next y
Print "|";
For y = 0 To 15
If RTCBUFF(I+y) >=32 And RTCBUFF(I+y)<=126 Then ' show ascii only
C$=Chr$(RTCBUFF(I+y))
Else
C$=" "
EndIf
Print C$;
Next y
Print "|"
wait
Next I
End Sub


' wait for any key
Sub wait prompt$
If prompt$<>"" Then Print prompt$
Do While Inkey$="":Loop
End Sub