Delta Tau PMAC Pack, Справочник по аппаратуре

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PMAC-Pack
PMACPack Custom Configuration 47
E3 - E6: Servo Clock Frequency Control
The servo clock (which determines how often the servo loop is closed) is derived from the phase clock
(see E29 - E33) through a "divide-by-N" counter. Jumpers E3 through E6 control this dividing function.
The setting of I-Variable I10 should be adjusted to match the servo interrupt-cycle time set by E98, E3 --
E6, E29 -- E33, and the master clock frequency. I10 holds the length of a servo interrupt cycle, scaled so
that 8,388,608 equals one millisecond. Since I10 has a maximum value of 8,388,607, the servo interrupt
cycle time should always be less than a millisecond (unless you want to make your basic unit of time on
PMAC something other than a millisecond). If you wish a servo sample time greater than one
millisecond, the sampling may be slowed in software with variable Ix60. Frequency can be checked on J4
pins 21 & 22.
Note:
If E40-E43 are set up so that the card has a software address other than @0, the
servo clock signal must be received over the serial port from card @0, so these
jumpers have no effect.
Table 4-4. E3 - E6: Servo Clock Frequency Control
E3 E4 E5 E6 Servo Clock = Phase
Clock Divided By N
Default & Physical Layout
E4 E4 E4 E4
ON ON ON ON N = divided by 1
OFF ON ON ON N = divided by 2
ON OFF ON ON N = divided by 3
OFF OFF ON ON N = divided by 4 Only E5 and E6 ON
ON OFF ON ON N = divided by 5
OFF ON OFF ON N = divided by 6
ON OFF OFF ON N = divided by 7
OFF OFF OFF ON N = divided by 8
ON ON ON OFF N = divided by 9
OFF ON ON OFF N = divided by 10
ON OFF ON OFF N = divided by 11
OFF OFF ON OFF N = divided by 12
ON ON OFF OFF N = divided by 13
OFF ON OFF OFF N = divided by 14
ON OFF OFF OFF N = divided by 15
OFF OFF OFF OFF N = divided by 16