Need help to interface TFT LCD with HX8357 with MCU Cortex M3

HI, This is sushant,

i have the 3.2 inch TFT LCD with HX8357C controller **broken link removed**.

I have developed a custom PCB using LPC1768, i have attached Schematic for controller and image for Interface Connector View attachment portable_LCDV1_PAGE1.pdf

Change in schematic is RESET pin has been disconnected from MCU RESET and attached to TP10. RS has been misspelled as RD.

the problem is couldnt get is run, the LCD is showing with screen. i have checked library with https://github.com/seanogden/HX8357_PIC32.

i couldnt actually target the problem, also i kind of confused with TFT controller naming, the one i have has HX8375C, but on github or any arduino example code (C++) i have found has HX8357B or D as mentioned.

also while checking SPI read write code, i can see NO read frame, read data is always 0xFF, i read datasheet for HX8357D000/1, it has mentioned 2 serial mode as 3 wire SPI or 4 wire SPI, so i think it may be 3 wire SPI, but i need to know the communication is proper or not.

I am using LPCOPen library, with C as programming language.

At present i am cluless and need some guidance to trouble shoot.

Any suggestion will be helpful,

Thanks sushant

First you make sure that your SPI is working - try send few bytes and get proper response. You should be able to read and write registers content.
Only then you can try write any code for lcd itself.

Easyrider83 said:

First you make sure that your SPI is working - try send few bytes and get proper response. You should be able to read and write registers content.
Only then you can try write any code for lcd itself.

Click to expand...

Thanks for your time and thoughts,

Yes i also thought checking SPI, i removed SPI and SHORTED MOSI and MISO pin, i could see the send frame in receive d buffer. so actually my concern is how do u check slave when there is not read operation ? all the library i have checked has no read operation.

Normaly I have SPI driver already working for 100%. If i'm not sure, I'm using logic analyzer like USBee (7$ from eBay). Then trying to read some registers with well known values, better something like ID or another read-only register.

Easyrider83 said:

Normaly I have SPI driver already working for 100%. If i'm not sure, I'm using logic analyzer like USBee (7$ from eBay). Then trying to read some registers with well known values, better something like ID or another read-only register.

Click to expand...

Hi, thanks for reply, i got it running but not by serial, i used parallel bus DB0-DB15, it was harding finding API, i got one with for AVR ARM controller, so LCD is working, it just i cant get it running on SPI, as u said its good idea to read but to my bad luck i found non API for this LCD driver with READ operation on SPI.

i would like to share my doubt may naive, i think my controller SPI bus is on 3.3v TTL level, and for LCD controller i am giving 5v as VIN, so willl that create a problem ?

Hi,

i got one with for AVR ARM controller,

Click to expand...

Afaik there is no "AVR ARM controller"
* either AVR controller
* or ARM controller

Klaus

I believe this TFT only supports 16 bit parallel interface for LCD driver, it has SPI interface for touch panel and SD card

Why no one wants to take a look at datasheet? IM0, IM1 and IM2 pins used to select interface.

KlausST said:

Hi,


Afaik there is no "AVR ARM controller"
* either AVR controller
* or ARM controller

Klaus

Click to expand...

Sorry its AVR 256.

- - - Updated - - -

Easyrider83 said:

Why no one wants to take a look at datasheet? IM0, IM1 and IM2 pins used to select interface.

Click to expand...

i did but those are not accessible for user, i have added the image for your reference,


ONLY SPI pin out and Data bus pin out is available

Yes i know those config options, but if you follow the datasheet all configuration pins and other inputs are not available on header, so you are limited to what you have on header. Try to take out TFT some time those configuration are available on the ribbon but you should be very careful working on that.

If you want SPI based TFT i would recommend to find TFT with only SPI interface. For this purpose i use Raspberry PI based TFT with SPI interface, there are a lot more TFTs available with SPI interface.

Moreover you can find TFT with configurations for 16bit, 8bit or SPI interface at https://www.buydisplay.com/