New ALE Features
AnyCalls
An AnyCall is a general broadcast similar to AllCall with the difference that it requests responses, without designating any specific addressee(s). Therefore, an ALE station may use the AnyCall to generate responses from essentially unspecified stations, and thus it can identify new stations and connectivities.
The global AnyCall address is @@?. As a variation, the calling station can also use selective AnyCall, which is identical in function to the global AnyCall, except that it specifies the last single character of the addresses of the desired subset of receiving stations (that is, it replaces the ? with an alphanumeric – see more details in Table 1). If even narrower acceptance and response criteria are required, double selective AnyCall may be used: this is identical to selective AnyCall, except that its special address (@AB) specifies the last two characters that the desired subset of receiving stations.
The operator can always initiate an outgoing (transmit) AnyCall, but the MICOM 2 can be programmed to accept or ignore incoming (receive) AnyCalls.
Any station accepting an AnyCall stops scanning, and then initiates a response in a randomly selected timeslot.
Self Addresses
Stations can also use their own self addresses when making calls. This may be useful for
The self address may be used only in
Null Address
The null address is a special type of address that is not directed to, accepted by, or responded to by any station.
This address is intended for test and maintenance purposes, and to provide buffer time: for example, if a null address appears in a group call, no station will respond in the associated timeslot.
Inlink Address
The inlink address, ?@?, is used to instruct all the stations participating in an already established link to accept and act upon the information sent with the inlink address. For example, any station can use the inlink address to send an AMD message that all the linked stations would present to their user.
The inlink address is recognized only after a link is established between two or more stations.
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