Instruction Manual

P/N 117167 rev. A 15
Banner Engineering Corp. • Minneapolis, MN U.S.A.
www.bannerengineering.com • Tel: [phone]
MINI-ARRAY
®
Two-Piece Measuring Light Screen
Appendix A
Assume that the system has 48 channels and the system detects weak alignment.
The transmit and receiver strings would be as follows:
Transmit string to sensor: 0xF4, 0x41, 0x66, 0x00, 0x64, 0xFE
Receive string from sensor: 0xF4, 0x41, 0x66, 0x06, 0x30, 0x00, 0x30, 0x00,
0x01, 0x00, 0xFD, 0xFD
This receive string would be interpreted as follows:
0xF4 is the start-of-header byte
0x41 is the sensor-identification byte
0x66 is the command requesting the sensor status information
0x06 is the number of data bytes
0x30 there are 48 emitter channels
0x00 all emitter channels are OK
0x30 there are 48 receiver channels (that’s good, because the emitter has 48
channels also!)
0x00 all receiver channels are OK
0x01 the system detects weak alignment
0x00 there are no degraded channels
The last two bytes are the check sum in low-byte, high-byte order.
Request Sensor to Transmit One or Two Measurement Values (Command 0x67)
This command requests the sensor to transmit the previous scan’s measurement
values (one or two measurement values). The command will transmit either two or
four bytes (as specified by the sensor configuration). Assume that the sensor ID
is 0x41 and the sensor is configured to transmit the First Beam Blocked and Total
Beams Blocked information. Also assume that the twentieth light channel happens
to be the first beam blocked and a total of 15 light channels are blocked.
Transmit string to sensor: 0xF4, 0x41, 0x67, 0x00, 0x63, 0xFE
Receive string from sensor: 0xF4, 0x41, 0x67, 0x04, 0x14, 0x00, 0x0F, 0x00,
0x3C, 0xFE
This receive string would be interpreted as follows:
0xF4 is the start-of-header byte
0x41 is the sensor-identification byte
0x67 is the command requesting the sensor measurement information
0x04 is the number of data bytes
0x14, 0x00 is the low-byte, high-byte integer value for the first beam
blocked = 20
0x0f, 0x00 is the low-byte, high-byte integer value for the total beams
blocked=15
The last two bytes are the check sum in low-byte, high-byte order. The check sum
is calculated as follows:
0xF4 + 0x41 + 0x67 + 0x04 + 0x14 + 0x00 + 0x0F + 0x00 = 0x1C3.
The ones complement of 0x1C3 = 0xFE3C.
Hence the low-byte, high-byte order would be 0x3C, 0xFE.