With A0,A1 and A2 not used for the I2C device address these 3-bits
select which of the eight 256 word blocks of memory are accessed.
In this case, for this device, you would use these 3-bits for block
selection and you can leave A0,A1 and A2 NC.

Try moving DPIN & CPIN over to portb and see what you get.

Sorry I don't have an F84A to wire-up & test, but this example below
does work with a 24LC16B wired to an F877 on a PICDEM 2 Plus
board. Just tested it. Works fine.

WP = gnd
DPIN & CPIN both pulled-up to Vcc through 4.7K resistors

DEFINE OSC 20

DPIN    var     PORTB.1           ' I2C data pin
CPIN    var     PORTB.2           ' I2C clock pin
B0      var     byte
B1      var     byte

Loop:
     For B0 = 0 To 15
         I2CWRITE DPIN,CPIN,$A0,B0,[B0]  ' Write address to itself
         Pause 10                ' Delay after write
    Next B0

    For B0 = 0 To 15
        I2CREAD DPIN,CPIN,$A0,B0,[B1] ' Read
        HSerout [DEC B1,13,10] ' Print
    Next B0
    PAUSE 250
    Goto loop

This definitely works.
Regards,

-Bruce
tech@rentron.com
http://www.rentron.com

>
>         Include "modedefs.bas"          ' Include serial modes
> DEFINE OSC 4
> DEFINE I2C_SCLOUT                       ' make clock pin bipolar
> DPIN    var     PORTA.3                 ' I2C data pin
> CPIN    var     PORTA.0                 ' I2C clock pin
> B0      var     byte
> B1      var     byte
> B2      var     byte
>
>         For B0 = 0 To 15                ' Loop 16 times
>                 I2CWRITE DPIN,CPIN,%1010000,B0,[B0]  ' Write each location's address to itself
>                 Pause 10                ' Delay 10ms after each write
>         Next B0
>
> loop:   For B0 = 0 To 15 step 2         ' Loop 8 times
>                 I2CREAD DPIN,CPIN,%1010000,$1,[B1,B2]        ' Read 2 locations in a row
>                 Serout PORTA.2,N9600,[#B1," ",#B2," "]       ' Print 2 locations
>         Next B0
>
>         Serout PORTA.2,N9600,[10]            ' Print linefeed
>
>         Goto loop
>
>
> I am using a 4MHZ crystal. The 24LC16B connections are:
> Vdd to +5
> Vss to GND
> A0-A2 to GND
> WP to GND
> SCL to a pull-up resistor 4.7K (it goes to VDD) and to PORTA.0 of pic
> CDA to a pull-up resistor 4.7K (it goes to VDD) and to PORTA.3 of pic
>

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