I2C backpack for 16x2 LCD

Hello guys,

does anyone know where i can get one similar to this?
http://www.ebay.com/itm/Board-Module-Port-IIC-I2C-TWI-SP-I-Serial-Interface-For-Arduino-1602-LCD-/301721785531?hash=item46400514bb:g:b6oAAOSw9N1V2vSO

but with PCF8574A (Note the “A” as i need the I2C address of the “A” version).

thanks.

If there is a specific reason to use the address for the PCF8574A? you can always re-assign the address with:

#define I2C_ADDR    0x27 //what ever addresss you need goes here. Addresses ranging from 0x38 to 0x3F

If you don't know your address you can run the I2C scanner sketch to find what address your LCD is using.

Hope it helps.

xchido: If there is a specific reason to use the address for the PCF8574A? you can always re-assign the address with:

#define I2C_ADDR    0x27 //what ever addresss you need goes here. Addresses ranging from 0x38 to 0x3F

If you don't know your address you can run the I2C scanner sketch to find what address your LCD is using.

Hope it helps.

yes there is, looking to work with a master which is permanenet at 0x38.

If there is a specific reason to use the address for the PCF8574A? you can always re-assign the address with . . .

He has stated his reason but there are others as well. What if he has more than eight displays in his system and he needs another bank of addresses.

Back to the original question "does anyone know where i can get one similar to this . . . but with PCF8574A (Note the "A" as i need the I2C address of the "A" version)."

It's seems to be pretty much of a crapshoot as to which chip they stuff in the board at assembly time. You will probably have to query each vendor to see what they have in stock at a particular time.

Don

what size package is that chip in all the cheapy boards? is it SOP16? maybe ill rework the PCB myself and replace chip.

I'm too old to have dealt much with surface mount components, I can barely see them.

The device on my adapter has a 'T' suffix and the plastic body of the chip is 10 mm long and 7mm wide.

Don

Yep, thats common today, im looking for one with AT version.

ONE possibility here: http://yourduino.com/sunshop2/index.php?l=product_detail&p=484

Disclaimer: Mentioned my own shop!!

terryking228: ONE possibility here: http://yourduino.com/sunshop2/index.php?l=product_detail&p=484

How does it become a possibility when it states on that page:

The default address is 0x27

Eh?

i3dm: Yes there is, looking to work with a master which is permanent at 0x38.

Well the question is of course, why would this "master" not be under your control; why would it be so foolishly hard-wired? :astonished:

This obviously must be some sort of repair of an obsolete device?

Paul__B: How does it become a possibility when it states on that page:Eh? Well the question is of course, why would this "master" not be under your control; why would it be so foolishly hard-wired? :astonished:

This obviously must be some sort of repair of an obsolete device?

its a device im trying to read data from, its not under my control and its hard wired.

terryking228: ONE possibility here: http://yourduino.com/sunshop2/index.php?l=product_detail&p=484

Disclaimer: Mentioned my own shop!!

Terry, the default address 0x27 implies you are selling the "T" chip while i specifically asked for "AT". do you have any "AT" chips on those expanders? if so let me know.

i3dm:
its a device I’m trying to read data from, its not under my control and its hard wired.

Though as much - in my “repair” category. :grinning: