As viewed looking at the rear of the LED panel. The panel is arranged as a 36row x 32col grid. LEDs are split into 16 left and 16 right columns, with every six rows driven by three cascaded drivers. From right to left, the first driver drives Red subpixels, the second Green and the third Blue. Anode voltage is switched to each of the six rows of LEDs in sequence via a transistor controlled by the CPLD.
There are three I2C devices on the LED panel, an EEPROM, a temperature sensor and an ambient light sensor used for brightness calibration.
Most of the LED driver control pins are brought out to the data connector by way of two buffers. The remaining signals (SOUT for each driver string) are fed to the CPLD.
Power connector:
4 | GND |
3 | GND |
2 | +4.56V |
1 | +4.56V |
Data Connector:
CPLD_PIN_6* | 60 | 30 | VIN |
CPLD_PIN_44* | 59 | 29 | VIN |
CPLD_PIN_43* | 58 | 28 | GND |
CPLD_PIN_42* | 57 | 27 | I2C_SDA |
CPLD_PIN_41* | 56 | 26 | I2C_SCL |
LED_GSCLK | 55 | 25 | LED_BLANK |
LED_XLAT | 54 | 24 | LED_MODE |
CPLD_PIN_8* | 53 | 23 | CPLD_PIN_2* |
CPLD_PIN_5* | 52 | 22 | CPLD_PIN_3* |
+3.3V | 51 | 21 | +3.3V |
+3.3V | 50 | 20 | +3.3V |
+3.3V | 49 | 19 | +3.3V |
+3.3V | 48 | 18 | +3.3V |
GND | 47 | 17 | GND |
GND | 46 | 16 | LED_XERR |
GND | 45 | 15 | LED_CAL_SIN |
LED_R6_SIN | 44 | 14 | GND |
GND | 43 | 13 | LED_R5_SIN |
LED_R4_SIN | 42 | 12 | GND |
GND | 41 | 11 | LED_L6_SIN |
LED_L5_SIN | 40 | 10 | GND |
GND | 39 | 9 | LED_L4_SIN |
LED_R3_SIN | 38 | 8 | GND |
GND | 37 | 7 | LED_R2_SIN |
LED_R1_SIN | 36 | 6 | GND |
GND | 35 | 5 | LED_L3_SIN |
LED_L2_SIN | 34 | 4 | GND |
GND | 33 | 3 | LED_L1_SIN |
GND | 32 | 2 | GND |
GND | 31 | 1 | LED_SCLK |
*CPLD pins are not yet mapped to functions. CPLD functions include cycling through rows, routing SOUT data from LED drivers, and six pins mapped to transistors scattered across the board with yet unknown function.
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