TS-7250-V3 LCD Header

From Technologic Systems Manuals

The LCD header is a 0.1" pitch 2x7 header including GPIO. This is designed around compatibility with the HD44780 LCD controller which includes our LCD-LED. The LCD Data pins (7-14) are 5V tolerant. These will output up to 3.3V, and the remaining control IO and PWM are 3.3V tolerant. The TS-7250-V3 Debian images include a command lcdmesg. This can be used to write to our LCD-LED display.

For example, this would write to the display:

lcdmesg "line 1" "line 2"
# Messages can also be piped to lcdmesg:
echo -e "line 1\nline 2\n" | lcdmesg

For example, running:

lcdmesg Technologic Systems

will display:

LCD LED example.jpg

Pin 4, the LCD_BIAS pin, is used to set the contrast on the LCD.

tshwctl --address 0x1c --poke16 0x0 # Writes minimum
tshwctl --address 0x1c --poke16 0xf # Writes maximum
Signals Pin Layout
Pin Signal
1 5V
2 GND
3 LCD_RS GPIO Bank 2 IO 21
4 LCD_BIAS [1]
5 LCD_EN GPIO Bank 5 IO 20
6 LCD_WR GPIO Bank 5 IO 19
7 LCD D1 GPIO Bank 2 IO 9
8 LCD D0 GPIO Bank 5 IO 10
9 LCD D3 GPIO Bank 5 IO 11
10 LCD D2 GPIO Bank 5 IO 12
11 LCD D5 GPIO Bank 5 IO 15
12 LCD D4 GPIO Bank 5 IO 16
13 LCD_D7 GPIO Bank 5 IO 17
14 LCD_D6 GPIO Bank 5 IO 18

TS-7250-V3-LCD Header.svg

  1. PWM duty cycle controlled by FPGA Syscon reg 0x1c. This may need to be tuned depending on the environment or altitude where the display is used.