Blinkenwall.com/Controller
| Language: | English |
|---|
Blinkenwall Controller
Case is from a Sun Cobalt RaQ 550. The controller for the Blinkenwall is an ODROID C1.
Front Panel
The front panel has the following connector:
| Function | Pin | Pin | Function |
|---|---|---|---|
| Display Enable | 1 | 2 | Transceiver !OE |
| GND | 3 | 4 | +5V |
| Display D1 | 5 | 6 | Display D0 |
| Display D3, Button Up | 7 | 8 | Display D2, Button Left |
| Display D5, Button Right | 9 | 10 | Display D4, Button Down |
| Display D7, Button S | 11 | 12 | Display D6, Button E |
| Display RS | 13 | 14 | Display R/W |
| GND | 15 | 16 | +5V |
| LED Cathode "Earth" | 17 | 18 | NC |
| LED Cathode "HD 1" | 19 | 20 | LED Cathode "LAN 1" |
| LED Cathode "HD 2" | 21 | 22 | LED Anode "Wrench" |
| LED Anode Power Button (two LEDs in parallel!) | 23 | 24 | LED Cathode "ETH 1" |
| LED Cathode "LAN 2" | 25 | 26 | Button Power (with HW debouncing) |
| GND | 27 | 28 | +5V |
| NC | 29 | 30 | NC |
| LED Cathode "ETH 2" | 31 | 32 | NC |
| NC | 33 | 34 | NC |
The transceiver is used so that you can put the display data pins and the buttons on the same GPIOs. It's a 74F245. The display is a HDM16216L-5-LCEP.
The voltage is 5V for everything, except for the buttons. These simply pull to GND and have a 4.7kΩ pullup.
Display
The display is HD44780-compatible. According to the book "Microcontrollers: From Assembly Language to C Using the PIC24 Family", it has TTL-level inputs, so 3.3V logic level can drive it. Thus, no logic level shifter is required.
LEDs
All LEDs except for the wrench and the power LEDs are common anode. Specs: If=10mA, Uf=~2.05V
All LEDs except for the wrench are green.
The two power LEDs are in parallel (wtf), Specs: If=20mA, Uf=2.04V
Wrench (orange!): If=10mA, Uf=2V
Thus, all LEDs except for the power LEDs need a 330Ω resistor. The power LEDs need a 150Ω resistor.
The 7 regular LEDs can be driven by a TLC6C598CQDRQ1. The power LEDs should be driven from the 5V supply of the ODROID C1 directly, the wrench is still an open question (what do we want to do with that?).
Cobalt RaQ Links
- http://www.t2-project.org/packages/lcdutils.html (lcdutils-0.2)
- https://github.com/uberlinuxguy/rpi-cobalt (docs)
