Product data

MFRC631 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2014. All rights reserved.
Product data sheet
COMPANY PUBLIC
Rev. 3.3 — 4 February 2014
227433 71 of 120
NXP Semiconductors
MFRC631
High performance ISO/IEC 14443 A/B reader solution
9.7.2.1 T0ReloadHi
High byte reload value of the Timer0.
9.7.2.2 T0ReloadLo
Low byte reload value of the Timer0.
Table 72. T0Control bits
Bit Symbol Description
7 T0StopRx If set, the timer stops immediately after receiving the first 4 bits. If
cleared the timer does not stop automatically.
Note: If LFO Trimming is selected by T0Start, this bit has no effect.
6- RFU
5 to 4 T0Start 00b: The timer is not started automatically
01b: The timer starts automatically at the end of the transmission
10b: Timer is used for LFO trimming without underflow (Start/Stop on
PosEdge)
11b: Timer is used for LFO trimming with underflow (Start/Stop on
PosEdge)
3 T0AutoRestart 1: the timer automatically restarts its count-down from T0ReloadValue,
after the counter value has reached the value zero.
0: the timer decrements to zero and stops.
The bit Timer1Irq is set to logic 1 when the timer underflows.
2- RFU
1 to 0 T0Clk 00b: The timer input clock is 13.56 MHz.
01b: The timer input clock is 211,875 kHz.
10b: The timer input clock is an underflow of Timer2.
11b: The timer input clock is an underflow of Timer1.
Table 73. T0ReloadHi register (address 10h);
Bit 7 6 5 4 3 2 1 0
Symbol T0Reload Hi
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Table 74. T0ReloadHi bits
Bit Symbol Description
7 to 0 T0ReloadHi Defines the high byte of the reload value of the timer. With the start
event the timer loads the value of the registers T0ReloadValHi,
T0ReloadValLo. Changing this register affects the timer only at the
next start event.
Table 75. T0ReloadLo register (address 11h);
Bit 7 6 5 4 3 2 1 0
Symbol T0ReloadLo
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