Wake-up light display

synopsis

Xopr salvaged a wake-up light display (it's in his project crate) At first it looked like dot matrix display driven by a sort of plain shift register, but apparently, it's a led-on-pcb 7 segment display with a punched sheet on top of it, and the 'shift register' has more features..

The display

technical details

It works on 5v, and has a Princeton technology corporation PT6964-S 28 pins, SOP IC (datasheet) on it.

The cable pinout is as followed

1. GND (red)
2. VCC, 5V
3. LCD-STB (strobe, process 8 bit command after falling edge, high means ignore clk)
4. LCD-CLK (clock, reads input at rising edge, writes output on falling edge)
5. LCD-DI, LSB first, shifts in on rising CLK edge

It has 4 commands:

• 00xxxxba: Display mode setting command
  • where ba is:
  • 00: 4 digits, 13 segments
  • 01: 5 digits, 12 segments
  • 10: 6 digits, 11 segments
  • 11: 7 digits, 10 segments
• 01xxdcba: Data setting command
  • where ba is:
  • 00: write data to display
  • 10: read key data
  • and c is address increment mode:
  • 0: increment after data has been written
  • 1: fixed address
  • and d is mode setting:
  • 0: Normal operation mode
  • 1: Test mode
• 11xxdcba: Address setting command
  • where dcba is ram address 0x00 to 0x0d
• 10xxdcba: Display control commands
  • where cba is dimming quality
  • 000 to 111 is : {1,2,4,10,11,12,13,14}/16 pulse width
  • and d is display settings:
  • 0: display off (scan continuous)
  • 1: display on

ideas

It has some interesting symbols on it:

1. Light symbol (sun)
2. colon: hour/minute separator
3. Clock time symbol (clock)
4. Alarm symbol (bell)
5. Radio symbol ('FM')
6. ’Birds’ sound symbol (twitter?)
7. ‘Beep’ sound symbol (wifi?)
8. ‘African jungle’ sound symbol (drum)
9. ‘Wind chimes’ sound symbol
10. Sleep timer symbol ('ZZz')
11. Display brightness symbol (moon?)
12. decimal separator
13. Sound level symbol

also see

Wake-up light sound chip