Issue 5610: the epoch-counter (smart-transducers-ftf) Source: Institut fuer Technische Informatik (Mr. Thomas Losert, thomas@vmars.tuwien.ac.at) Nature: Uncategorized Issue Severity: Summary: The former usage of the epoch counter (one epoch lasts from one MSA round to the next) sets some constraints about the max. number of slots available for MP rounds. It is easier implementable and more convenient if the epoch counter implicitely is incremented witch each fireworks byte. As an additional advantage the pair (epoch counter, slot counter) can be used as timestamp in the ST cluster. Thus these values should be made available in the IFS for application tasks. Resolution: The meaning of the epoch is changed. In addition to the values "epoch counter" and "slot counter" the "currently assigned cluster name", the "number of the current round", and the current state of the nodes protocol is made available in the "Configuration File (file no. 0x08)". Supporting the epoch counter is an optional service for an ST. Since the maximum length of an MP round has been based on the horizon of the slot-counter this also influences the maximum length of a MP round. Another constraint is the length of the owner file (see issue XXXX). Thus the length of an MP round is limited to 64 Slots. Resolution: see above Revised Text: 9/29/02 Page 25 Section 2.3.8 “Global Time”, prelast paragraph: [...] The epoch of the time scale at a slave (internal time representation) begins with the instant of the start of a firework. Every time a new round (MP, MSA, or MSD round) is started the 8-bit epoch counter is incremented by one. Thus each slave can distinguish between 256 consecutive epochs. Smart Transducers FTF Finalization Task Force Report Disposition: Accepted OMG Issue No: 5611 In order to allow a slave to (re)integrate to the system the master transmits its 8-bit epoch-counter with each MSA round. This 8-bit epoch counter replaces the cluster name in the MS address round which is not needed any more at the addressed master. Section 2.4.3 (new version of picture, description of the additional values): Sleep IDCV Header Record Byte 0x01 0 3 0x02 0x03 0x04 0 0 0 3 3 3 MSB LSB 0x05 0 3 CLN NLN CCN SCTR ECTR CRND STAT CCN: is the Currently assigned Cluster Name. STAT: is the current Status of the node. CRND: is the number of the current round. ECTR: is the current value of the Epoch-Counter. SCTR: is the current value of the Slot-Counter. Section 2.8.2 “Timing”, first paragraph: Whenever the master sends a firework for a new round … Section 2.8.2 “Timing”, third paragraph: Since the maximum length of a MP round is 78 slots (fireworks plus up to 62 data bytes plus up to 15 slots for Inter Round Gap) and the slot counter is reset to 0x00 with the beginning of each epoch (at the beginning of each round), the slot counter easily fits into an 8 bit register. Thus the pair epoch counter and slot counter may be used as timestamp on ST level. Since every cluster can have differing transmission speeds (and time formats) the master must transform the internal time representation to the external time representation. Section 3.3 “Optional Requirements”: Maintain Epoch Counter This function enables a slave to maintain the Epoch Counter and thus provide timestamps within an ST. Actions taken: August 27, 2002: received issue December 11, 2002: closed issue Discussion: The meaning of the epoch is changed. In addition to the values “epoch counter” and “slot counter” the “currently assigned cluster name”, the “number of the current round”, and the current state of the nodes protocol is made available in the “Configuration File (file no. 0x08)”. Supporting the epoch counter is an optional service for an ST. Since the maximum length of an MP round has been based on the horizon of the slot-counter this also influences the maximum length of a MP round. Another constraint is the length of the owner file (see issue 5611). Thus the length of an MP round is limited to 64 Slots. End of Annotations:===== Title: the epoch-counter (smart-transducers-ftf) Source: TTTech Computertechnik AG (Mr. Thomas Losert, thomas@vmars.tuwien.ac.at) Summary: The former usage of the epoch counter (one epoch lasts from one MSA round to the next) sets some constraints about the max. number of slots available for MP rounds. It is easier implementable and more convenient if the epoch counter implicitely is incremented witch each fireworks byte. As an additional advantage the pair (epoch counter, slot counter) can be used as timestamp in the ST cluster. Thus these values should be made available in the IFS for application tasks. Resolution: The meaning of the epoch is changed. In addition to the values "epoch counter" and "slot counter" the "currently assigned cluster name", the "number of the current round", and the current state of the nodes protocol is made available in the "Configuration File (file no. 0x08)". Supporting the epoch counter is an optional service for an ST. Since the maximum length of an MP round has been based on the horizon of the slot-counter this also influences the maximum length of a MP round. Another constraint is the length of the owner file (see issue XXXX). Thus the length of an MP round is limited to 64 Slots. Revised Text: Section 2.3.8 "Global Time", prelast paragraph: [...] The epoch of the time scale at a slave (internal time representation) begins with the instant of the start of a firework. Every time a new round (MP, MSA, or MSD round) is started the 8-bit epoch counter is incremented by one. Thus each slave can distinguish between 256 consecutive epochs. In order to allow a slave to (re)integrate to the system the master transmits its 8-bit epoch-counter with each MSA round. This 8-bit epoch counter replaces the cluster name in the MS address round which is not needed any more at the addressed master. Section 2.4.3 (new version of picture, description of the additional values): CCN: is the Currently assigned Cluster Name. STAT: is the current Status of the node. CRND: is the number of the current round. ECTR: is the current value of the Epoch-Counter. SCTR: is the current value of the Slot-Counter. Section 2.8.2 "Timing", third paragraph: Since the maximum length of a MP round is 78 slots (fireworks plus up to 62 data bytes plus up to 15 slots for Inter Round Gap) and the slot counter is reset to 0x00 with the beginning of each epoch (at the beginning of each round), the slot counter easily fits into an 8 bit register. Thus the pair epoch counter and slot counter may be used as timestamp on ST level. Since every cluster can have differing transmission speeds (and time formats) the master must transform the internal time representation to the external time representation. Section 3.3 "Optional Requirements": Maintain Epoch Counter This function enables a slave to maintain the Epoch Counter and thus provide timestamps within an ST. Disposition: Accepted