CE Labs SW404HD, SW808HD, SW404, SW808 Addendum

CE Labs, Inc. SW404 / SW808 Switch Protocol April 4, 2008

Addendum – Additional RS232/RS485 protocol information

CRC calculation:

The CRC is calculated as below. The CRC is optional for commands sent to the switch. If the
CRC is not used, bit 6 in first byte of command packet should be set to 0, otherwise 1 to utilize
the CRC. Note: A CRC byte is always appended to responses from the unit.

CRC-8-Dallas/Maxim x8 + x5 + x4 + 1 (1-Wire bus) 0x31 or 0x8C (0x19)

Polynom 31H
Inverted 8CH
Initial 00H
Final Xor 00H
Input Data Reversed (Reflected)
Final Result Reversed (Reflected)

Command Examples:

Numbers are Hex Bytes. Requests are shown with CRC and without CRC.
The response is the same whether or not CRC is appended to request

*******************************************************************

Request machine info and model

Request: 20 3F 00 00 F1 (or 00 3f 00 00)
Response: 80 0A C4 04 04 59 58 2D 33 30 34 34 C8
Y X - 3 0 4 4

Audio and video supported, 4 output x 4 input,
4 memory locations, name = YX-3044

*******************************************************************

Request audio status for all, put in memory location 0

Request: 20 08 00 00 55 (or 00 08 00 00)
Response: 80 08 01 04 02 00 03 00 04 00 65

Output 1 to Input 4, Output 2 disconnected,
Output 3 disconnected, Output 4 disconnected

Rev. A

CE Labs, Inc. SW404 / SW808 Switch Protocol April 4, 2008

Command Examples (continued):

*******************************************************************

Request video status for all, put in memory location 0

Request: 20 07 00 00 0A (or 00 07 00 00)
Response: 80 08 01 04 02 00 03 00 04 00 65

Output 1 to Input 4, Output 2 disconnected,
Output 3 disconnected, Output 4 disconnected

*******************************************************************

Switch audio output 1 to input 4

Request: 20 02 01 04 9A (or 00 02 01 04)
Response: 80 8C <- simple ack

*******************************************************************

Request audio status for output 1, put in memory location 0

Request: 20 08 01 00 91 (or 00 08 01 00)
Response: 80 02 01 04 33 <- output 1 connected to 4

*******************************************************************

Switch video output 1 to input 4

Request: 20 01 01 04 7E (or 00 01 01 04)
Response: 80 8C <- simple ack

*******************************************************************

Request video status for output 1, put in memory location 0

Request: 20 07 01 00 CE (or 00 07 01 00)
Response: 80 02 01 04 33 <- output 1 connected to 4

Error in Manual:

The Supported Output Port and Supported Input are simply numbers representing the number of
ports. Individual bits do not represent ports as shown in manual. The corrected version is below:

Supported Output Port (ACK Type C)

SOP7 SOP6 SOP5 SOP4 SOP3 SOP2 SOP1 SOP0

Number of supported output ports

Supported Input Port (ACK Type C)

SIP7 SIP6 SIP5 SIP4 SIP3 SIP2 SIP1 SIP0

Number of supported input ports

Rev. A