iNS/iDS 2-Wire System Manual
350-077
Rev. D - 1/20/2021
Page 67 of 107
If using an SDLC cable in BIU Mode (no Cable A and no Cable C) :
The NEMA TS 2 2003 specification defines SDLC command and response frames for 4 detector BIUs. The iCCU-S2
can be configured to operate as any one of these four BIUs for the purpose of placing pedestrian calls to the Traffic
Controller. Typically, there are 4 pedestrian phases (2, 4, 6 and 8), however the iCCU-S2 can be configured for up to
8 pedestrian phases. By default, detector BIUs are used to places vehicle calls in the Traffic Controller. In order to use
the iCCU-S2 configured as a detector BIU, the Traffic Controller needs to be programmed to map the vehicle call
inputs to pedestrian call inputs. The process to do this varies by Traffic Controller. Consult your Traffic Controller
manual or manufacturer for instructions on how to do this.