Cirrus Logic CobraNet - Manual (Page 111)

CobraNet Programmer’s Reference
Management Interface Variable Reference
DS651PM25
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Copyright 2006 Cirrus Logic, Inc. 111
Name syncClockTrim
Description
Allows fine control of clock rate when acting as a network conductor in internal synchronization
mode (syncConductorClock = 0x00). Range of control is on the order +/-37PPM
A trim value of 0xFFFFFF is sufficient for most applications.
0xFFFFFF - normal
0x800000 - minimum frequency
0x7FFFFF - maximum frequency
For RAVE only:
0x500000 - normal
0x7FFFFF - minimum frequency
0 - maximum frequency
Host Address
0x60002
SNMP Object ID
1.3.6.1.4.1.2680.1.1.8.3
Type
Integer
Attributes Read/write - Persistent
Default Value Read from flash configuration record.
Implemented Version
2.2.1
Name
syncBuddyLinkControl
Description
BuddyLink allows two CobraNet interfaces to operate as a redundant pair with fail-over capability.
The BuddyLink signal must be synthesized in hardware by ANDing together the FS1 clock and
MUTE signals from the primary interface. Presence of this gated clock signal at the REFCLK_IN
input of the Secondary unit indicates proper operation of the Primary unit. Mute is asserted
(dropped) when a fault is detected by the primary, which then gates off the clock signal to the
secondary. As long as the BuddyLink signal is detected by the secondary unit, it will send empty
reservation requests preventing the unit from transmitting and, in most cases, receiving audio.
When absence of the clock is detected, the secondary will begin transmitting valid reservation
packets, thus allowing it to process bundles. An idle secondary unit may still receive multicast
bundles. The following values may be OR’d together:
0x2 - Disable reference clock input. This master disable feature should be invoked on designs
where the reference clock input is not connected. Disabling the reference clock input prevents noise
from interfering with operation of the interface.
0x4 - Enable BuddyLink. Presence of a clock at REFCLK_IN will disable network transmitters and
receivers.
0x8 - Force Buddy Link presence. Applicable in secondary BuddyLink interfaces to simulate failure
of a primary BuddyLink partner. Enable BuddyLink bit is overridden.
Host Address
0x60003
SNMP Object ID 1.3.6.1.4.1.2680.1.1.8.4
Type
Integer
Attributes
Read/write - Persistent
Default Value
2
Implemented Version
2.4.7