Specifications
ISU AT Command Reference  Phase IV AT Commands 
Iridium Proprietary Version 2.45 
20 June 2011     64 
8.6  +CSSSC – Supplementary Services Short Code 
Exec Command: +CSSSC=”<shortcode>” 
Execute the given shortcode. If the shortcode fails, a CME ERROR code is returned. Otherwise, OK is 
returned. 
Note: Shortcode functionality is only available if provisioned. 
Note: This command is supported on 9555 / 9555A Handsets only. 
Note: This command does not support command concatenation. 
8.7  +WIRLP - Iridium Radio Link Protocol 
Set Command: +WIRLP=[<ver>[,<k1>[,<k2>[,< t1>[,<n2>[,<t2>[,<r1>[,<r2>[,<t4>[,<mode>]]]]]]]]]] 
Set desired IRLP parameters to be negotiated with the peer at the start of the next data call. Note that these 
desired parameters are reset to hardcoded defaults at the end of a data call, so this command should be 
issued while a call is not in progress. 
  <ver> specifies the desired IRLP version and can take the following values: 
    0  Default IRLP version (N0) 
  <k1> represents the maximum number of sequentially numbered I frames that may be outstanding 
      at any given time at downlink direction (IWF->ISU) and can take the following values: 
      1-105. Default is 105. 
  <k2> represents the maximum number of sequentially numbered I frames that may be outstanding 
    at any given time at uplink direction (ISU->IWF) and can take the following values: 
    1-105. Default is 105. 
  <t1> is used to supervise the acknowledgment of transmitted unnumbered frames. The values are 
  defined to be the earliest instant to enter the recovery procedure and can take on the 
   following values: 27-255 (in 50-ms unit). Default is 30. 
  <n2> is used to represent the maximum number of re-transmission attempts of a frame (e.g. 
    I,S,N,U frame) and can take on the following values: 1-255. Default is 15. 
  <t2 > is used to indicate the amount of time available within the acknowledging frame must be 
    transmitted and can take on the following values: 1-255 (in 10-ms unit). Default is 10. 
  <r1> is used to represent the maximum number of S frames that are used to acknowledge I frames 
    at downlink direction (IWF->ISU) and can take on the following values: 1-10. Default is 10. 
  <r2 > is used to represent the maximum number of S frames that are used to acknowledge I frames 
    at uplink direction (ISU->IWF) and can take on the following values: 1-10. Default is 10. 
  <t4 > is used to supervise the re-sequencing of miss-ordered frames. The values are defined to be 
    the earliest instant to consider a tardy frame as lost. It can take on the following values: 
    20-255 (in 10-ms unit). Default is 25. 
  <mode> is used to indicate the mode of operation and can take on the following values: 
    0  unacknowledged mode of operation 
    1  acknowledged mode of operation (default) 










