Sierra Video Yosemite - Manual (Page 71)

505150 PROCESSORS
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Non-volatile RAM
The control processor board contains battery-powered RAMS, which are used to store the crosspoint
matrix state, mapping information, salvo presets, source/destination/input/output/level names, control
panel configuration, source/destination restrictions, output lockouts, and other non-volatile information.
Any information stored in the non-volatile RAM remains there when the switcher is powered down. The
software checks the information for validity at power-up time, and if valid, refrains from initializing it. This
allows the switcher to largely maintain its state between power-ups. After verifying the data validity
following a power-up, all crosspoints are reloaded using the non-volatile data, to the value they last had
when the processor board was previously running, unless DIP switch S1-5 (505150) is on, in which case
they are set to 1-1, 2-2, etc. (If there are more destinations than sources, after reaching the last source,
the sources are recycled over again.)
It is possible to force re-initialization of the non-volatile RAM. This is not recommended, because all
existing customization and configuration data will be lost, and it can be a lengthy procedure to restore the
data. However, in some cases it makes sense to reinitialize the non-volatile RAM. The factory should
always initialize the RAM of a new router, if non-volatile RAMS that were already initialized in another
router are used. To accomplish a re-initialization, turn on DIP switch S1-8 (505150) or DIP Switch S2-8
(504001), power up the router, power it down, and turn off S1-8 (505150) or S2-8 (504001). If for any
reason a customer decides to do this, it is highly recommended that they record as much of their router
setup data as possible, using terminal protocol to access the data.
IMPORTANT NOTE: A special version number is stored in non-volatile RAM. If the software is changed
such that the structure or arrangement of data in non-volatile RAM has changed, this version number
(located in ramcheck.c) must be incremented. This will force a re-initialization of the non-volatile RAM
when the new software is installed into an older router. Consult SVS Customer Service.
Input, Output, and Level Names
The control processor board supports only long names for sources, destinations, inputs, outputs, and
level names. Long names have from 1 to 8 characters. Names can be applied using TyLinx Pro (see the
TyLinx Pro manual), or via the terminal port (see Communication Protocol Chapter 8)
Source and destination names apply to all levels, while input and output names are assigned on a level-
by-level basis.
Any attempt to assign source, destination, input, output, or level names that contain invalid characters or
more than 8 characters, are rejected. Valid characters are any printable ASCII character from space (hex
20) to tilde (hex 7E), except asterisk (hex 2A) and exclamation (hex 21).
If the last characters of a source, destination, input, or output name are digits, they become the name
suffix
, a value from 1 to 255 (one less than the maximum currently supported by the Yosemite processor),
and the beginning part is the prefix. If the ending digits are a number larger than this, some of the ending
digits are kept as part of the prefix.
Some control panels are able to assign pushbuttons to prefixes, providing a convenient way for the user
to select inputs and outputs mnemonically by pressing a prefix button and then keying in the numeric
suffix using a numeric keypad.
The control processor board supports separate names for each input and output on each level. However,
there is a limit to the total number of unique name prefixes (that part of the name preceding a numeric
suffix). If this limit is exceeded, the name will remain unchanged when an attempt is made to change it.
On the Yosemite / Tahoe control processor boards, the limit is 512 (505150) and 128 (504001) total
unique prefixes (source, destination, input, and output prefixes combined).