Colour graphics demo for a 1.8" TFT Display

[cfbsoftware]

The attached zip file contains the source code of the Graphics line-drawing functions, ST7735 TFT display driver and a demo program to be used with v7.0 Astrobe for RISC5.

It displays AutoCAD Slide images of St Paul's Cathedral and the Columbia space shuttle on an 1.8" TFT Display:

Slide.jpg (86.66 KiB) Viewed 72450 times

The command used to run the demonstration module is SlideDemo.Run Columbia.sld or SlideDemo.Run StPauls.sld

The screen we used is the AdaFruit 1.8" Colour TFT Shield (PID: 802) which conveniently plugs into the Arduino-compatible headers on the Digilent Arty A7 and S7 boards.

[mrlx]

Would you mind posting a list of the hardware items shown in the photo? I would like to recreate it exactly and am more of a software person than a hardware one. Thank you.

[cfbsoftware]

The items shown in the photo are:

1. Development board: Arty S7 Development board
2. Screen: AdaFruit 1.8" Colour TFT Shield (PID: 802)
3. MicroSDHC Card adapter: Opus-Two Micro SD-card Adapter for Xilinx ARTY FPGA Evaluation Kit

The following is not required to run the Slide demo:
4. Realtime Clock: SparkFun DeadOn RTC Breakout - DS3234

If you already have Embedded Project Oberon running on an Arty A7 or S7 board the only additional item you will need is the screen. No wiring is involved; it plugs directly into the Arduino-compatible socket on the Arty board.

[mrlx]

I have the Arty S7 working with the RISC5 code using the provided examples. However, I have not been able to get the SlideDemo or TextDisplay samples to work. The Adafruit 1.8" TFT LCD Shield works when connected to an Arduino Uno but not when connected to the Arty S7. One oddity is that my Shield looks somewhat different than the one in the forum. For example, mine has a 6-pin ICSP connector next to the microSD. Any suggestions, please, on what I might try to get this working? (I attempted to attach a photo of my setup(861KB) but the forum rejected it as being too large.)

[cfbsoftware]

I checked the AdaFruit website and it appears that you have 'Version 2' which is significantly different to 'version 1' Unfortunately they are currently out of stock of the latest version so I have asked them to notify me when they are back in stock again.

[mrlx]

I have three. I will be happy to ship you one particularly if you are willing to take a look at my problem.

[cfbsoftware]

Thank you for your offer but no need to worry. I've since ordered one from Digi-Key who have 60+ in stock.

[cfbsoftware]

I'm sorry about the delay but I have only just been able to allocate the resources to revisit this issue. Although the physical SPI connectors used are different from v1 they should map onto the existing ones. The next issue is that the backlight is now PWM controlled via I2C through a separate onboard microcontroller! I can't see a way of bypassing this and using the GPIO pin that we used in v1 just to switch the backlight on/off. It might just work if that could be done.

Aside from the broken backwards compatibility, this v2 version of the shield has become far too complex for our simple requirements. Even worse, it is is now physically incompatible with our Nucleo 64 / 144 STM32 ARM boards. Consequently we will have to source an alternative solution. In the meantime, I recommend that you try to acquire a v1 version of the board - there were still a few being advertised when I first investigated the problem.

[cfbsoftware]

Because of the problems reported previously in this discussion I've decided to now support the ST7735 TFT Display driver library and associated demos on the simpler AdaFruit 1.8" Color TFT LCD display with MicroSD Card Breakout:

https://www.adafruit.com/product/358

I have tested it on both the Arty S7 and the STM32 Nucleo L152RE boards and both work with the existing code. The Breakout board: Arty S7 connections are as follows:

Code: Select all

LITE:    IO5
MISO:     -
SCK:     IO13
MOSI:    IO11
TFT-CS:  IO10
CARD-CS:  -
D/C:     IO8
RESET:   IO6
VCC:     3V3
Gnd:     GND

[mrlx]

Sorry for all the trouble but thanks for the Christmas present.