What display have I received

[frankie53]

I ordered a 20x4 LCD display to use with my Arduino (see Ordered) and received something which looks a little different (see Delivered).

Can anyone help me identify just what I have received and point me to a datasheet for it so that I can drive it correctly?

Many thanks if you can.

 

[danadak]

"Usually" these character displays Hitachi / Renesas 44780 compatible controller.


Regards, Dana.

 

[Pommie]

The delivered one appears to have I²C interface as well as the "normal" parallel interface. Not sure how that works. Do you have a datasheet?

Mike.
Edit, my guess would be that the missing components on the left side are the I²C interface and it's a normal parallel interface as ordered.

 

[danadak]

Normally used to seeing I2C as a small add on module :

Regards, Dana.

 

[danadak]

I ordered a 20x4 LCD display to use with my Arduino (see Ordered) and received something which looks a little different (see Delivered).

Can anyone help me identify just what I have received and point me to a datasheet for it so that I can drive it correctly?

Many thanks if you can.

Contact the seller for more info ?

Regards, Dana.

 

[Nigel Goodwin]

Normally used to seeing I2C as a small add on module :

I agree, that's usually how it's done - I suspect that it's just a normal Hitachi style module, and the I2C style pins are for a different product, perhaps one that utilises one or more of the empty IC mounts on the board? (it even has I2C address selection points near the empty U7 position). Perhaps they make an alternative version with I2C built-in?.

I wonder what the missing U6 (on both boards) is for?.

For the OP - I wouldn't even have hesitated, presumably you ordered an Hitachi style display, and there's VERY little reason to think you've got anything else. Connect it to your Arduino, and you should be good to go.

 

[danadak]

You could use this pinout, try a couple of tests, take a R, say 100 ohms, and connect
power to the backlight pin thru the R to see if that matches pinout and backlight
comes on.

http://www.systronix.com/access/Systronix_20x4_lcd_brief_data.pdf

If it does then connect main power to display, and measure drop across 100 ohm to see
what display current drain is. I = V / R. If it looks like roughly the current drain of the
display, a few mA, then this pinout probably good. For the other I/O pins use a couple
of hundred ohms in series with display pins as protection to not destroy display if its not
what we think. And if display seems to work then remove R's. Typically with no input, but
powered up, you might see something like this (contrast pin not adjusted) :

Regards, Dana.

 

[Nigel Goodwin]

Funnily enough, I've just fitted five 2x16 Hitachi style displays - they also have a missing IC (like U6 above), except it's labelled U3.

 

[rjenkinsgb]

It will be fine.

Note that they are both model "2004A", the one you have received is just an updated version.
(Use the original datasheet).

 

[frankie53]

Many thanks for all the useful responses. I shall initially try connection to the I2C pins to determine if they work and if they don't I will use the data pins.

 

[augustinetez]

It won't work with I2C - if you look up in the top left of your 'delivered' pic, you will see the address setting pads labelled A0,1,2 - the I2C components that they connect to are not mounted.

 

[Nigel Goodwin]

Many thanks for all the useful responses. I shall initially try connection to the I2C pins to determine if they work and if they don't I will use the data pins.

So why ignore them? - we've all said use the 16 data pins - there is no I2C.

 

[danadak]

If yiou need I2C there are cheapo adapter boards out there :

i2c to lcd for sale | eBay

Get the best deals for i2c to lcd at eBay.com. We have a great online selection at the lowest prices with Fast & Free shipping on many items!

www.ebay.com

Regards, Dana.