Raymarine ST6000 Service Manual page 131

Channel 4
Channel 5
Channel 6
Channel 7
IC9 Channel 0
Channel 1
Channel 2
Channel 3
Channel 4
Channel 5
Channel 6
Channel 7
1.5 Clutch Drive
TR10, 11 and 12 switch a nominal 12v onto the actuator clutch whenever pin 15 of
the microprocessor (IC2) is low at 0v.
1.6 Seatalk Bus Transmit and Receive
Seatalk transmit and receive circuitry consists of TR1,3,4,5,18 and 19 and their
associated components. Data transmission is at 4800 baud with a low start bit and
line idling high. TR1 and Tr2 provide high and low drive respectively, whilst TR3 and
R1 give overload protection to Tr2 in the event of misconnection. Tr4 and Tr5 allow
the microprocessor to monitor its own transmissions and also to receive data from
other units on the bus.
1.7 Fluxgate drive
IC2 produces bursts of 8KHz pulses on pin 2 which are then fed through Tr6,7 and 8
and AC coupled to the fluxgate via C3.
1.8 E2 prom
2
IC8 is an E PROM which allows calibration values to be stored and recalled each
time after power up. Sequential data is written to the e2 prom on pin 3 and read
back on pin 4.
1.9 Supply voltage monitor
R53 and R54 scale down the supply voltage and feed it through to the A/D converter
to enable the microprocessor to transmit a warning on the Seatalk bus if the supply
voltage drops below 11.2v for 10 seconds or more.
Feedback 1 (FB1)
Feedback 2 (FB2)
Not used
Not used
Not used
Not used
Rudder Reference (RUDDER)
Supply Monitor (INPUT VOLTS)
Not used
Not used
Joystick
Not used
Autohelm Autohelm
Autohelm Autohelm
SeaTalk Service Manual 3