NXP Semiconductors MPC5644A, Reference Manual, Page: 850 / 1735

Enhanced Time Processing Unit (eTPU2)
MPC5644A Microcontroller Reference Manual, Rev. 6
850 Freescale Semiconductor
NOTE
If a transition occurs simultaneously (after the filter) with the CHAN
assignment, PSS samples the new pin value. Therefore, if TDLA/B is
cleared simultaneously with the assignment CHAN := CHAN, the
occurrence of a transition at this very moment can still be tested with PSS.
PRSS – Pin Request Service Sample
Channel logic can, depending on its state and programmed mode, request service to the eTPU microengine
(see
Section 24.5.1, Functions and threads ). When the channel logic issues a service request, the filtered
input signal PSTI is sampled into an internal channel flag PRSS. There is one such PRSS flag for each
channel (see
Figure 24-37 ). Channel PRSS keeps its value until all its service request sources are cleared
and until a new service request rises.
The channel PRSS flag is sampled into the branch logic as the PRSS flag (see Table 24-113 ) during the
time slot transition period, or whenever the CHAN register is written by microcode.
OBE – Output Buffer Enable control latch
OBE latch drives the Output Buffer Enable signal, which can be used (depending on MCU integration) to
control the output signal pad driver. Channel output comes disabled from reset. If ipp_obe_[1|2]([0-31])
1
from eTPU is used on MCU integration and a signal is desired to be output in a channel, OBE signal must
be set by microcode. Microcode field TBSA is used to set/reset the Output Buffer Enable control when
microcode field TBSA bit 3 is 1, according to
Table 24-46
.
1. Output Buffer Enable: there is one independent OBE signal for each channel.
Table 24-46. TBSA Output Buffer control
Microcode TBSA[2:0] meaning when TBSA[3] = 1
000 enable output buffer
001 disable output buffer
111 do nothing
other values reserved