NXP Semiconductors PN544 C2 - Presence Check of ISO14443 A Card: Use NXP_WR_PRESCHECK; Handling of Multiple Type a Readers

NXP Semiconductors
UM191812
PN544 C2 User Manual
191812 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2010. All rights reserved.
User Manual Rev. 1.2 — 2010-06-16 136 of 172
9.15.3.2 Presence check of ISO14443A card: use NXP_WR_PRESCHECK
Whe
n the reader wants to check the presence of the ISO14443 card in the field, it shall
send the command NXP_WR_PRESCHECK. In ISO14443, the PN544 will send a
R(NAK) block to the card. It expect R(ACK) or last I block in response, as defined in
ISO14443-4.
9.15.4 Handling of multiple Type A readers
Both the UICC and the host can activate a reader session at the same time.
The next figure shows a simplified view of the system.
Secure Element
Contactless card
I2C or SPI or HSU
SWP
HOST
RF
Technology
(type A)
Reader
RF gate
Type A
Reader
application
Reader
application
gate
UICC
Type A
Reader
application
Reader
application
gate
NFC WI
PN544
antenna
Fig 71. Simplified system view