4. Send pan value half speed = 128 + (64/2) = Hex A0 within 1mS.
5. Send CRC value, in this case Hex 116 + Hex 01 + Hex A0 = 1D7
after radix to 8 bits = B7.
6. This completes the transmission.
RECEIVING FROM A LAMP
Lamps broadcast data sequentially. There is no need to actively request data
to be sent, just wait for the lamps address with bit 7 set to be present on the
bus and load the next six bytes. An example is given below; -
EXAMPLE
Obtain lamp number 2 pan position.
1. Listen to the data bus and wait for value Hex 112. (Lamp addresses
start at hex 10 so lamp 2 is value 12. Addresses always have bit 8 set
so total value is Hex 112).
2. Load the next six bytes from the bus.
3. If desired check the last of the six bytes which is the CRC.
4. Read the two bytes which will be a value centred on 2048 increasing
for clockwise from centre and decreasing for anticlockwise. This is
lamp number 2 current pan position.
FBUS Speed Control Assembly Status LED Operation
Overview
The FBUS motor control card has a status LED near the top of the card
(labelled
‘STATUS’). This has several functions as detailed below.
SOFTWARE VERSION
When power is applied to the speed control card the status LED will flash
green. The number of flashes corresponds to the software version.
FBUS NORMAL OPERATION
When the system is operating from FBUS the status LED will illuminate static
green. When a valid FBUS data signal is received the LED will switch off
momentarily to indicate data reception. If data is continuous the LED will flash
green slowly.
