mfrc522 NXP Semiconductors, mfrc522 Datasheet - Page 13

• Manufacturer Part Number: mfrc522
• Description: Contactless Reader Ic
• Manufacturer: NXP Semiconductors

NXP Semiconductors
112132
Product data sheet
9.2.1.1 Reserved
9.2.1.2 CommandReg
9.1.1 Register Bit Behavior
9.2.1 Page 0: Command and Status
9.2 Register Description
Depending on the functionality of a register, the access conditions to the register can vary.
In principle bits with same behavior are grouped in common registers. In
access conditions are described.
Table 6:
Functionality is reserved for further use.
Table 7:
Table 8:
Starts and stops command execution.
Abbreviation Behavior
r/w
dy
r
w
RFU
RFT
Bit
7 to 0
Symbol
Access
Rights
Bit
Symbol
-
Behavior of Register Bits and its Designation
Reserved register (address 00h); reset value: 00h
Description of Reserved register bits
7
read and write These bits can be written and read by the μ-Controller. Since they
dynamic
read only
write only
-
-
Rev. 3.2 — 22 May 2007
6
Description
Reserved for future use.
Description
are used only for control means, there content is not influenced by
internal state machines, e.g. the ComIEnReg-Register may be
written and read by the μ-Controller. It will also be read by internal
state machines, but never changed by them.
These bits can be written and read by the μ-Controller.
Nevertheless, they may also be written automatically by internal
state machines, e.g. the Command-Register changes its value
automatically after the execution of the actual command.
These register bits hold values which are determined by internal
states only, e.g. the CRCReady bit can not be written from
external but shows internal states.
Reading these register bits returns always ZERO.
These registers are reserved for future use and shall not be
changed. In case of a write access, it is recommended to write
always the value “0”.
These register bits are reserved for future use or production test
and shall not be changed.
5
4
RFU
-
3
2
Contactless Reader IC
MFRC522
© NXP B.V. 2007. All rights reserved.
Table 6
1
the
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