User's Manual

Turbo PMAC PCI HRM
Main Board E-Point Descriptions 21
E34 - E38: Encoder Sampling Clock Frequency Control
Jumpers E34 - E38 control the encoder-sampling clock (SCLK) used by the gate array ICs. No more than
one of these six jumpers may be on at a time.
SCLK Clock Frequency
Default and
Physical Layout
E34A E34 E35 E36 E37 E38
E34A E34 E35 E36 E37 E38
A4 A4 A4 A4 A4 A4
ON OFF OFF OFF OFF OFF 19.6608 MHz
OFF ON OFF ON OFF OFF 9.8304 MHz E34 On
OFF OFF ON OFF OFF OFF 4.9152 MHz
OFF OFF OFF ON OFF OFF 2.4576 MHz
OFF OFF OFF OFF ON OFF 1.2288 MHz
OFF OFF OFF OFF OFF ON External clock 1 to 30 MHz
maximum output on CHC4
and CHC4/
E40 - E43: Software Address Control
Jumpers E40–E43 control the software address of the card, for serial addressing and for sharing the servo
and phase clock over the serial connector. Card @0 sends the clocks and cards @1–@F receive the clocks.
Card Address Control
E Points
Default and Physical Layout
E40 E41 E42 E43
E40 E41 E42 E43 Card Address
LOCATION B5 B5 B5 B5
ON ON ON ON @0 @0
OFF ON ON ON @1
ON OFF ON ON @2
OFF OFF ON ON @3
ON ON OFF ON @4
OFF ON OFF ON @5
ON OFF OFF ON @6
OFF OFF OFF ON @7
ON ON ON OFF @8
OFF ON ON OFF @9
ON OFF ON OFF @A
OFF OFF ON OFF @B
ON ON OFF OFF @C
OFF ON OFF OFF @D
ON OFF OFF OFF @E
OFF OFF OFF OFF @F
Note: The card must be set up either as @0, or receiving clock signals over the serial port from another
card that is set up as @0, or the Watchdog timer will trip (red light on) and the card will shut down.