Single Wire Protocol
From Wikipedia, the free encyclopedia
The Single Wire Protocol (SWP) is a specification for a single-wire connection between the SIM card and a near-field communication (NFC) chip in a cell phone. It was under final review by the European Telecommunications Standards Institute (ETSI)[when?].[1][2]
SWP is an interface between contactless frontend (CLF) and universal integrated circuit card (UICC/SIM card chip). It is a contact-based protocol that is used for contactless communication. C6 pin of UICC is connected to CLF for SWP support. It is a bit-oriented full-duplex protocol, i.e. transmission and reception are possible at the same time. CLF acts as a master, and UICC as a slave. CLF provides the UICC with energy, a transmission clock, data, and a signal for bus management. The data to be transmitted are represented by the binary states of voltage and current on the single wire.
