STM32F4 Discovery + HY32D TFT LCD

25 May 2012

I am working on a project to create a touch screen that will enable the user to control a robotic device whilst receiving data and video from the device controlled.

I am completely new to TFT LCD technology, and was slightly daunted by the complexity of these devices. I am still on the uphill of the learning curve...

The STM32F4 Discovery boardSTM32F4 Discovery board has an FSMC ( Flexible Static Memory Controller ) which supports the connection of an LCD in parallel mode. I have 3 STM32F4 Discovery boards, so I decided to use one to control the HY32D TFT LCD I bought off Ebay, with absolutely useless example code for an 8051 type microcontroller.

There are a few examples on the web of the STM32F4 Discovery used in projects with the same controller that the HY32D uses, the SSD1289 from Soloman Systech Ltd.

The table below lists the connections used in the fractal drawing program...the touch control is not yet used.

LCD pin name	STM32F4 Pin number	STM32F4 pin name
D0	61	PD14
D1	62	PD15
D2	81	PD0
D3	82	PD1
D4	38	PE7
D5	39	PE8
D6	40	PE9
D7	41	PE10
D8	42	PE11
D9	43	PE12
D10	44	PE13
D11	45	PE14
D12	46	PE15
D13	55	PD8
D14	56	PD9
D15	57	PD10
CS	88	PD7 (NE1)
RS	60	PD11 (FSMC-A16)
RD	85	PD4 (NOE)
WR	86	PD5 (NWE)
RESET		+3V(1K Pull up) or GPIO
TP_IRQ		PD6
TP_SCK	52	PB13
TP_SI	54	PB15
TP_SO	53	PB14
TP_CS	51	PB12
BL_CNTL	69	PA10

I will send code for the fractal drawing to whoever asks, just send me your email. I have now (12/06/2012) also added it to Google project hosting.

It should be available to download here.

The code is not mine, a very helpful fellow Engineer sent it to me.

I will be working on creating a touch menu next and will update soon hopefully.

Update: 3/06/2012

I have managed finally to convert a .jpg image into a C array and get it displayed on the HY32D TFT LCD, touch screen works also, although I do have to write a better calibration routine.

I converted the .jpg using the RGB565 converter from ST Micro which is available as part of the STM Embedded resources GUI

Decided to start on a touch menu now...could not resist putting direction arrows on..left, right, up, and down, and next a menu button in the middle. Why? Well I am taking small steps and will work up to displaying data next, to start with I am going to attempt to write a calibration routine for the touch screen, and then get each button to control direction of 2 DC motors...eventually the buttons will operate a circuit designed to transmit a 'direction signal' using 2.4GHz RF.

a pic of the screen so far...4 buttons no menu yet, each arrow is 50x50 pixels in size.

A word of caution...I am using IAR Embedded Workbench for ARM version 6.30.8. I had to increase the STACK size to be able to store these images..no point me going into too much detail, as I do not yet quite understand it properly, if you have the same problems let me know and I can at least guide you through what I have done so far...