PCF7936AS/3851/C,1-CT NXP Semiconductors, PCF7936AS/3851/C,1-CT Datasheet - Page 15

• Manufacturer Part Number: PCF7936AS/3851/C,1-CT
• Description: pcf7936as series 32-bit 125 khz read / write security...
• Manufacturer: NXP Semiconductors

NXP Semiconductors
Security Transponder (HITAG2)
HALT
The command HALT may be issued in AUTHORIZED state
and forces the device to enter the HALT state. For data
integrity reasons the 5 bit command and its complement
have to be send, before the device will accept it, see
Figure 10. If accepted, the command Response consist of
the command itself and its complement.
The 10 bit command sequence may be repeated several
times, if desired, to increase the data integrity level. In the
case that one of the 5 bit commands and its complement
do not match, an error condition occurs that causes the
device to terminate the command, to initialize the device
and to enter the WAIT state. No command Response will
be send by the device in this case.
If the device is configured for Password mode (ENC = 0)
the command sequence is transmitted in plain, while in
Cipher mode (ENC = 1) the whole command sequence is
transmitted ciphered.
2010 May 04
Figure 10. HALT timing
Figure 11. READ_PAGE timing
SEND to
Transponder
RECEIVED from
Transponder
SEND to
Transponder
RECEIVED from
Transponder
1 1, pg2, pg1, pg0
READ_PAGE
CM[4:0]
0 0 0 0 1
CM[4:0]
HALT
0 0, pg2, pg1, pg0
CM[4:0]
1 1 1 1 0
CM[4:0]
15
READ_PAGE
The command READ_PAGE returns the content of the
designated page. The page designated for reading is
specified by the command bits pg2 to pg0. For data
integrity reasons the 5 bit command and its complement
have to be send, before the device will accept it, see
Figure 11. If accepted, the command Response consists of
the 32 bit content of the designated page. The MSB is send
first.
The 10 bit command sequence may be repeated several
times, if desired, to increase the data integrity level. In the
case that one of the 5 bit commands and its complement
do not match, an error condition occurs that causes the
device to terminate the command, to initialize the device
and to enter the WAIT state. No command Response will
be send by the device in this case.
Subsequent commands may be issued after termination of
t
Any attempt to read a page that is protected against
reading, will be detected and cause an error condition,
upon which the device terminates the command during
t
send in this case.
If the device is configured for Password mode (ENC = 0)
the command sequence is transmitted in plain, while in
Cipher mode (ENC = 1) the whole command sequence is
transmitted ciphered.
WAIT,Bs
WAIT,Tr
1 1 1 1 1
EQ
1 1 1 1 1
t
.
WAIT,Tr
EQ
and enters the WAIT state. No Response will be
t
WAIT,Tr
bit 31 ..................... bit 0
CM[4:0]
0 0 0 0 1
Data
1 1 1 1 0
CM[4:0]
Product Specification
PCF7936AS
CONFIDENTIAL
t
WAIT,Bs