[ARM] Can STM32F107 drive KS0108 or HD47780 directly ?

[bianchi77]

Guys,
I want to use 16x2 or 128x64 LCD with STM32F107, is it possible ?
Can STM32F107 drive KS0108 or HD47780 directly ?

Any ideas ?
thanks

 

[wp100]

Hi,

The ST chips datasheet says it I/Os are rated at Standard TTL and CMOS loads so no problem there, but the voltage level could be a problem.

If the ST is run at 3.3 /3.6v technically that should produce a '1' on a 5V LCDs input, however thats not a certainty, though I would try it first.
If not then there are several low to high voltage converters you could use, the CD40109 for one such device.

Wonder why you want to use the old KS0108 ( library available ?) when there are so many good and low priced modern SPI GLCDs around

 

[alexan_e]

If you are using uni directional communication with the display then you can use any 74HCT logic gate with 5v supply like for example 74HCT244.
The HCT series use TTL levels so anything above 2v is considered high and will give 5v to the output and anguishing below 0.8 a low level

On the other hand if you want bi-directional communication then you can use a mosfet for each line like shown https://delphys.net/d.holmes/hardware/levelshift.html

The complete schematic (for 8bit) looks like

 

[bianchi77]

do you mean like this :
https://www.ebay.com.au/itm/12864-128x64-GLCD-Graphic-LCD-Module-Display-SPI-Serial-ST7565P-3V-Black-White-/291022273441?pt=LH_DefaultDomain_0&hash=item43c2477ba1

But I don't have a library for it ??

 

[alexan_e]

The schematic I have attached is referring to an interface for HD44780 display

 

[bianchi77]

can I use 74HCT244 for 3.3V (MCU) and 5V LCD ? or 74HCT245 ? I tried to connect directly, there's a response but not stable...sometimes on sometimes off...
thanks

 

[alexan_e]

if the communication direction in only one way, from mcu to display then the 74HCT244 will work fine but the 74HCT245 is a transceiver, if you use it with direction from display to mcu it will fed the mcu with 5v and damage it