vme create mapname ?options? base size
vme delete mapname
vme list
name get -l|-w|-b offset
name set -l|-w|-b offset value
The vme command allows you to create, destroy and list a set of address windows into the VME card crate. Maps are named entities. When a map is created, the package also creates a command named after the map. This command is then used to access them map via its ensemble get and setcommands.
Creates a new map. The mapname parameter is the name of the map and, on success, is created as a new command that can be used to access them. base and size define the address window base address and size.
The following options are recognized:
-device typeDefines the address modifier associated with this map. This should be one of extended (32 bit address space), standard (24 bit address space), shortio (16 bit address space) or geo (slot addressing for crates and modules that support this.
-crate nSelects a VME crate other than the default crate 0. If not provided this defaults to zero.
Deletes an existing map. All device and driver resources are destroyed. The command created to access the map is removed from the interpreter.
Lists the set of VME maps defined by this script via this package. The maps are returned as the command result. The result is a list of two element sublists. Each sublist contains, in order, the name of the map and the base address of the map in VME space.
When a VME map is created, the name of the map also becomes a new Tcl command. That command is a command ensemble that allows your script to access the address window defined by the map.
A Tcl command ensemble is a command that has subcommands. The subcommands the map has are get which fetches data fromt he address window and put which puts data into the address window.
The format of the mapname get command is:
THe format of the mapname put command is:
These commands have some common elements. Specifically, offset is a byte offset into the map at which the get or put is performed. width is anoption which describes the width of the data transfer. This can be any of:
-lTransfer will be of longword (32 bit) width.
-wTransfer will be of word (16 bit) width.
-bTransfer will be of byte (8 bit) width.
The data on the put
subcommand is the data that is actually written to the VME
bus. Only the appropriate number of low order bits is used.