Specific ideas for interfaces built around the Arduino Uno.

Unless otherwise noted, all of the following require one of the following:

• tactile switches
  • likely interfaced with PCF8574 (about $1.59)
  • Digi-Key tact switches that take caps.
  • Digi-Key tact switch caps (non-illuminated; some Eswitch options seem to be missing).
  • This cap and these switches: 320, JN
• capacitive switches using an IC.
  • These as buttons.

• TODO

• \$5.50 + switches
• Very small
• Based on ST7735
• 1.8“ 160×128
  • eBay's alice1101983: Q=2@$11.35, Q=1@$6.64, a variant@$8.21
  • About \$5 to \$7 from other China on eBay ( 1, 2).
  • About $10 from USA on eBay ( 1).
  • East Rising has ILI9163-based versions around \$6+, possibly with optional touch.
  • Adafruit's version is around \$20!!
• 1.44” 128×128 can be had for about $3 from China.
• Current tests suggest it's too data-intensive for realtime use for the Uno.

• \$6 to \$12 + switches
• Bezel makes things potentially ugly.
• Using I2C (PCF8574 or MCP2008) with Arduino BigCrystal or Arduino BigCrystalTWI.
  • Converter module for ~\$1.
• Easy s/w design.
• alice1101983 blue: \$3.92 (\$19.84 for 5), yellow-green: \$4.26; + \$1.85 shipping
• East Rising ERM2004FS-1 20×4 black on white FSTN parallel: $10.30
• East Rising ERM2004DNS-1 20×4 white on black FFSTN parallel: $11.68

• \$10 (or ~\$2/character) + switches
• Potential s/w complexity.
• Limited number of characters and flexibility.
• Really begs for capacitive switches.
• alice1101983 MAX7219-based single@$3.52, Q=2@$5.20, Q=5@$10.07, Q=10@$18.27

• Around \$2 to \$3 from China (plus shipping).
• About 1.33“ diagonal size.
• SparkFun's page has good info.
• The actual LCD parts are surplus/pulls from phones.
• my experience with one of these points to potential reliability issues.

• \$12 (less in quantity or if you want to slum it with STN from China) + switches
• Bezel makes things potentially ugly.
• Dated?
• Example cheap STN from China, 128×64 ST7920: \$4.90 + \$1.99
  • Same but from USA: \$10.99
• East Rising FSTN ERM12864FS-6, 2.9” 128×64 SPI ST7920 black on white: \$8.41 + \$4.05
• East Rising STN ERM12864SBS-6 2.9“ 128×64 SPI ST7920 white on blue: \$11.56
• East Rising ERC12864FS-655, 2.8” 128×64 SPI ST7920 black on white w/ opt. touchscreen: \$6.26 + \$4.05
• Lots of 128×64 OLED options as well, e.g. this 2.42" SPI for \$19.77 + \$1.85 or this for \$19.75 or this for \$26.95.

• \$16 + shipping and up
• Tact switches possibly not required — but only the enhanced 7“ has capacitive touch.
• Lots of graphic image generation time needed (“style by image,” not “style by text”).
• 2.4" basic 320×240: \$16.40
• 2.4" enhanced 320×240: \$20.40
• 2.8" basic 320×240: \$18.40
• 2.8" enhanced 320×240: \$22.40
• 3.2" basic 400×240: \$22.40
• 3.5" basic 480×320: \$27.40
• 4.3" basic 480×272: \$44.90

• $19 + shipping + switches
• Lifetime issues
• Waveshare 2.9" module, 296×128 SPI: \$18.99 + shipping

• The UNO is probably too slow for anything larger than 200×200 pixels.