 |
Electronic Components Datasheet Search |
|
|
Electronic Components Datasheet Search |
|
PM73121 Datasheet(PDF) 77 Page - PMC-Sierra, Inc |
|
|
|||||||||||||||||||||||||||||
PM73121 Datasheet(HTML) 77 Page - PMC-Sierra, Inc |
|
|
77 / 223 page  PM73121 AAL1gator II PMC-Sierra, Inc. PMC-980620 ,VVXH AAL1 SAR Processor Data Sheet QSPQSD@U6S`Ã6I9Ã8PIAD9@IUD6GÃUPÃQH8TD@SS6ÃDI8Ã6I9ÃAPSÃDUTÃ8VTUPH@ST¶ÃDIU@SI6GÃVT@ • If the line is in SDF-MF mode and R_CHAN_NO_SIG = 1 in the R_MAX_BUF word (refer to “R_MAX_BUF Word Format” on page 157), then the queue is handled as if it is in SDF-FR mode. The structure should be adjusted from a multiframe structure to a frame structure. For example, a channel with two DS0s would have a structure size of two bytes when R_CHAN_NO_SIG is set and a structure size of 49 bytes (include two signaling nibbles) if in T1 mode when R_CHAN_NO_SIG is off. 3.6.2 Underrun The AAL1gator II declares an underrun condition for a VC when no data is present in the VC receive buffer. When this situation occurs, the AAL1gator II plays out conditioned data and old signaling from multiframe 0 onto the timeslots assigned to the VC experiencing underrun. Timeslots generated by other VCs are unaffected. Each time a cell is received after a queue has entered an underrun condition, the UNDERRUN sticky bit is set. RALP does not know about an underrun until a cell is received for the queue that underflowed. To make sure that each underrun is counted only once, RALP will increment the R_UNDERRUN counter when exiting the under- run state and entering the resume state. The initial underrun caused by reset is not counted. Forced underruns due to other errors are not counted by the underrun counter. If the underrun counter is read and the queue is currently in underrun, the present underrun condition will not be accounted for until the queue exits underrun. To determine if the queue is in underrun, check the level of the R_UNDERRUN bit in the R_LINE_STATE register. When not in UDF-HS mode, the choice of conditioning data and signaling while in underrun depends on the value of RX_COND in the R_CH_QUEUE_TBL. Three choices exist: • Play out the data from R_COND_DATA and the signaling from multiframe 0 (Default). • Play out pseudorandom data and the signaling from multiframe 0. (For applications that are sensitive to constant data.) The pseudorandom data option uses the data from R_ COND_DATA and then replaces the most significant bit with the result of an 18th order polynomial, specifically x18 + x7 + 1. • Play out old data and the signaling from multiframe 0. (Also for applications that are sensitive to constant data.) The old data option replays out the contents of the data in the receive buffer for that channel. Data is played out from the location of the read pointer. Therefore, the oldest data is played out first. If in UDF-HS mode and in underrun, the data played out is the conditioned data defined for line 0, channel 0. There is no old data or pseudorandom data options available for UDF-HS mode. If the data is structured, the RALP searches for a new pointer, and finds the start of the structure. In all cases the RALP queues up data for one CDVT worth of time before exiting the underrun condition. The R_UNDERRUN bit in R_LINE_STATE word of R_QUEUE_TBL indicates if the queue is in an underrun state. The UNDERRUN sticky bit is set each time a cell is received during the underrun condition. Cells received while the pointer and start of structure are being located are |
|
Link URL |
| Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Contact us | Privacy Policy | Link to Datasheet | Link Exchange | Manufacturer List All Rights Reserved©Alldatasheet.com |
| Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
|
Family Site : ic2ic.com |
icmetro.com |
English ▼
English
Chinese
German
Japanese
Russian
Korean
Spanish
French
Italian
Portuguese
Polish
Vietnamese
Indian
Mexican
British
New Zealand
