NXP Semiconductors MPC5644A, Reference Manual, Page: 897 / 1735

Enhanced Time Processing Unit (eTPU2)
MPC5644A Microcontroller Reference Manual, Rev. 6
Freescale Semiconductor 897
Figure 24-53. TCR2 in Angle Mode
This 24-bit free-running counter is used to generate an accumulated Angle Fraction value. It is updated by
the Angle Tick Generator (refer to
Section 24.5.7.4, Angle tick generator , for more details). Refer to
Section 24.5.7.5, Count control and high rate logic , for a detailed explanation about the use of this register
in Angle Mode.
TCR2 provides continuous count of the angle in units of angle ticks. The Angle Tick Counter in TCR2 can
be reset due to “Last Tooth” microcode indication. TCR2 Prescaling is disregarded in Angle Mode:
physical tooth detection is done by EAC regardless of the value set in TCR2P.
24.5.7.2.3 TRR – Tick Rate Register
The exact period of the Angle Tick is programmed in the Tick Rate Register by microcode. The period of
the Angle Tick is given in units of TCR1 clocks as system clocks divided by 2*(TCR1P + 1), even if
TCR1CS = 1 (see
Section 24.4.3.1, ETPU_TBCR – eTPU Time Base Configuration Register ). Refer to
Section 24.5.7.4.1, Calculating the angle tick period integer and fraction , for a complete description about
the mechanism to calculate the value to be written into this register.
Figure 24-54. TRR Register
INTEGER[14:0]—The integer part of TCR1 clocks in one Angle Tick.
This number, decremented by one, works as a down-counter preload value. A value of INTEGER = 0
represents an integer of 32768. A new value written is reloaded into the counter (becoming effective)
when a new tick starts or a tooth is detected or inserted via IPH.
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16
R 0 0 0 0 0 0 0 0 Angle Tick Counter[23:16]
W
Reset 0 0 0 0 0 0 0 0
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
R Angle Tick Counter[15:0]
W
Reset 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
31 30 29 26 27 26 25 24 23 22 21 20 19 18 17 16
R 0 0 0 0 0 0 0 0 INTEGER[14:7]
W
Reset 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
R INTEGER[6:0] FRACTION
W
Reset 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0