MFRC52201HN1/TRAYB NXP [NXP Semiconductors], MFRC52201HN1/TRAYB Datasheet - Page 30

• Manufacturer Part Number: MFRC52201HN1/TRAYB
• Description: Contactless reader IC
• Manufacturer: NXP [NXP Semiconductors]

NXP Semiconductors
MFRC522_33
Product data sheet
PUBLIC
The timer can be started manually using the ControlReg register’s TStartNow bit and
stopped using the ControlReg register’s TStopNow bit.
The timer can also be activated automatically to meet any dedicated protocol
requirements, by setting the TModeReg register’s TAuto bit to logic 1.
The time delay of a timer stage is calculated with
below:
Example: To indicate 100 s, 678 clock cycles must be counted, so the TPrescaler value
must be set to 677 using register TModeReg bits TPrescaler_Hi[3:0] and TPrescalerReg
bits TPrescaler_Lo[7:0]. This gives the timer an input clock of 100 s that enables it to
count up to 65535 time slots for each 100 s.
Maximum time
•
•
TPrescaler reload value = 4095
TReloadVal reload value = 65535
=
4096
Rev. 3 — 26 October 2009
------------------------ -
6.78 MHz
65536
112133
=
39.59 s
Equation 5
adding 1 to the reload values
Contactless reader IC
MFRC522
© NXP B.V. 2009. All rights reserved.
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