TS-7250-V3 LCD Header

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:

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 IO Type Signal 1 5V 2 GND 3 CPU 3.3V LCD_RS GPIO Chip 20a4000.gpio IO 21 4 CPU 3.3V LCD_BIAS 5 CPU 3.3V LCD_EN GPIO Chip 50004010.fpga_gpio IO 20 6 CPU 3.3V LCD_WR GPIO Chip 50004010.fpga_gpio IO 19 7 CPU 3.3V+QS3861 LCD D1 GPIO Chip 20a4000.gpio IO 9 8 CPU 3.3V+QS3861 LCD D0 GPIO Chip 50004010.fpga_gpio IO 10 9 CPU 3.3V+QS3861 LCD D3 GPIO Chip 50004010.fpga_gpio IO 11 10 CPU 3.3V+QS3861 LCD D2 GPIO Chip 50004010.fpga_gpio IO 12 11 CPU 3.3V+QS3861 LCD D5 GPIO Chip 50004010.fpga_gpio IO 15 12 CPU 3.3V+QS3861 LCD D4 GPIO Chip 50004010.fpga_gpio IO 16 13 CPU 3.3V+QS3861 LCD_D7 GPIO Chip 50004010.fpga_gpio IO 17 14 CPU 3.3V+QS3861 LCD_D6 GPIO Chip 50004010.fpga_gpio IO 18