Dell LCD

Some Dell servers have a little monochrome LCD to show error messages and configuration menus. It is attached to the secondary SPI port.

[667056.909] SSPI.WR 0, time  20, mode 00, speed  14, [19,0]  e2 ae 7a a2 a0 c8 a6 21 81 28 2c 2e 2f e4 84 e6 03 a4 af -> 
[667056.910] SSPI.WR 0, time  20, mode 00, speed  14, [4,0]  46 b0 00 10 -> 
[667056.911] SSPI.WR 1, time  20, mode 00, speed  14, [132,0]  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 -> 
...
[667057.031] SSPI.WR 0, time  20, mode 00, speed  14, [4,0]  46 b1 00 10 -> 
[667057.032] SSPI.WR 1, time  20, mode 00, speed  14, [128,0]  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 -> 
[667057.034] SSPI.WR 0, time  20, mode 00, speed  14, [4,0]  46 b2 00 10 -> 
[667057.035] SSPI.WR 1, time  20, mode 00, speed  14, [128,0]  00 38 7c e4 c4 c4 8c 08 00 04 04 04 fc fc 04 04 04 00 c0 c0 00 00 00 00 00 00 18 1c 84 84 84 fc 38 00 00 38 7c e4 c4 c4 8c 08 00 00 fc fc 84 84 84 cc 78 30 00 00 f0 f8 8c 44 c4 9c 18 00 04 04 04 fc fc 04 04 04 00 00 c0 30 0c fc fc 00 00 00 00 00 fc fc 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 -> 
[667057.037] SSPI.WR 0, time  20, mode 00, speed  14, [4,0]  46 b3 00 10 -> 
[667057.050] SSPI.WR 1, time  20, mode 00, speed  14, [128,0]  04 0c 18 10 10 19 1f 0f 00 00 00 00 1f 1f 00 00 00 00 18 18 00 00 00 00 00 00 0c 1c 10 10 10 1f 0f 00 04 0c 18 10 10 19 1f 0f 00 00 1f 1f 00 00 00 00 00 00 00 00 07 0f 18 10 18 0f 07 00 00 00 00 1f 1f 00 00 00 00 03 02 02 02 1f 1f 02 02 10 10 10 1f 0f 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 -> 

Observations

• GPIO1.5 (21) is used to distinuish commands and data. When transmitting commands, the GPIO is low, during pixel data it is high.
• The display is organized in rows of 8 pixels in height by 128 pixels in width
• A command of the form 46 b0 00 10 selects the display row (b0 = row 0, b1 = row 1, etc.)
• pixels are stored LSB up: The uppermost pixel in a row is the least significant bit in pixel data, etc.

Front panel module

The front panel module consists of two boards

Horizontal board

Connectors

J_PLANAR connects the horizontal board to the mainboard, with a 50-pin ribbon cable.

description	pin	pin	description
?	1	2	GND
?	3	4	GND
?	5	6	GND
?	7	8	GND
?	9	10	GND
?	11	12	GND
GND	13	14
GND	15	16
?	17	18
?	19	20
?	21	22
GND	23	24	GND
?	25	26	SW_PWR
?	27	28	SW_NMI
?	29	30
?	31	32
?	33	34	LED DS1
TMP75 V+	35	36	GND
GND	37	38	USB D?
USB D?	39	40	GND
GND	41	42	SW_LCD
?	43	44	GND
TMP75 SCL	45	46	GND
TMP75 SDA	47	48	GND
?	49	50

Components

• SMSC USB2514-AEZG USB hub, between J_PLANAR and the two USB connectors.
• TMP75 temperature sensor. ALERT is N/C. A0-2 are set to the same value.

LCD board

The LCD board has the following markings:

Back:

20-20757-4
EDT REV.B

EW50878BMW
0922*A1G

Front:

EP-02 94V-0

Connectors

J_LCD connects the horizontal board with the LCD board.

pin	J_PLANAR	description
1	N/C
2	21
3	various	GND
4	20
5	14
6	various	GND
7	N/C	SW1 (Left)
8	various	GND
9	N/C	SW3 (Right)
10	various	GND
11	N/C	SW2 (Ok)
12	various	GND
13	19	SW4 (Info)
14	33,35
15	33,35
16	11
17	9
18	7
19	5
20	N/C