MFRC522 datasheet(13/109 Pages) NXP

13 / 109 page

112132

Product data sheet

Rev. 3.2 — 22 May 2007

13 of 109

NXP Semiconductors

MFRC522

Contactless Reader IC

9.1.1 Register Bit Behavior

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 Table 6 the

access conditions are described.

9.2 Register Description

9.2.1 Page 0: Command and Status

9.2.1.1

Reserved

Functionality is reserved for further use.

9.2.1.2

CommandReg

Starts and stops command execution.

Table 6:

Behavior of Register Bits and its Designation

Abbreviation Behavior

Description

r/w

read and write These bits can be written and read by the

μ-Controller. Since they

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.

dynamic

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.

read only

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.

write only

Reading these register bits returns always ZERO.

RFU

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”.

RFT

These register bits are reserved for future use or production test

and shall not be changed.

Table 7:

Reserved register (address 00h); reset value: 00h

Bit

Symbol

Access

Rights

RFU

Table 8:

Description of Reserved register bits

Bit

Symbol

Description

7 to 0

Reserved for future use.

MFRC522 Datasheet(PDF) 13 Page - NXP Semiconductors

MFRC522 Datasheet(HTML) 13 Page - NXP Semiconductors

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Datasheet Download

Link URL