System Overview

::System Hardware Overview::

Original Power Supply:

The large blue power supply provides 5v to the light board and the Arduino Mega.

New Multiple PSU:

There are now 6 PSUs, 1 per 4 G35 strings. Power to the Arduino Mega bypasses the relay board.

Display Board:

GE G35 Light strings are formed into a 24 row by 48 column display board.

Lights:

There are 48 lines of 24 G35 Christmas lights connected to an Arduino Mega. The 24 lines that make up the rows of the display have been cut in half to facilitate driving data to only 24 lights, which reduces the total time needed to send data.

Ports:

The following AVR ports are completely used for the display - A B C F K L

Pins:

string	pin	notes
pow1	14	to relay board
pow2	15
pow3	16
pow4	17
pow5	18
pow6	19
1	22	PORTA
2	23
3	24
4	25
5	26
6	27
7	28
8	29
9	53	PORTB
10	52
11	51
12	50
13	10
14	11
15	12
16	13
17	37	PORTC
18	36
19	35
20	34
21	33
22	32
23	31
24	30
25	A0	PORTF
26	A1
27	A2
28	A3
29	A4
30	A5
31	A6
32	A7
33	A8	PORTK
34	A9
35	A10
36	A11
37	A12
38	A13
39	A14
40	A15
41	49	PORTL
42	48
43	47
44	46
45	45
46	44
47	43
48	42

::System Software Overview::

Memory:

The frame buffer uses up 4K of the available 8K of RAM. Leaving less than 4K available for additional code. The first 1248 bytes of the EEPROM are filled with the Baltimore Node logo. The next 640 bytes of the EEPROM are filled with the 5x8 font.

Color Constants:

All colors are represented by the LS12B of an unsigned int. Format – 4 Brightness, 4b Blue, 4b Green, 4b Red.

The following color constants have been added for ease of use.

RED
BLUE
GREEN
PURPLE
YELLOW
CYAN
ORANGE
WHITE
BLACK