PXD10RM Datasheet, PDF (271/1332 Pages) Freescale Semiconductor, Inc – PXD10 Microcontroller

SRV3 SRV2 SRV1 SRV0
Time Slot selector bits
Real-time signalbus
(16-bit wide)
REDC
time base
output
Figure 9-40. REDC block diagram
Bits SRV[0:3] in register EMIOSMCR, selects the desired time slot of the real-time signal bus to be output.
Figure 9-41 shows a timing diagram for the REDC.
Real-time signal bus (REDC input)
TS[00] TS[01] TS[02]
TS[n]¹ TS[00] TS[01] TS[02]
time base (REDC output) xx
TS[01]
NOTES: 1. Maximum of 16 Time Slots (TS[n])
2. In this case, SRV bits were set to capture TS[01]
TS[01]
Figure 9-41. Timing diagram for the real-time signal bus and REDC output
Every time the selected time slot change, the REDC output is updated.
9.5.3.1 Effect of Freeze on the REDC
When the FRZ bit in the EMIOSMCR register is set and the module is in debug mode, the operation of
REDC submodule is not affected, i.e., there is no freeze function in this submodule.
9.5.4 Global Clock Prescaler Submodule (GCP)
The GCP divides the system clock to generate a clock for the CPs of the channels. The main clock signal
is prescaled by the value defined in Figure 9-10 according to the GPRE[0:7] bits in EMIOSMCR register.
The global prescaler is enabled by setting the GPREN bit in the EMIOSMCR register and can be stopped
at any time by clearing this bit, thereby stopping the internal counters in all the channels.
In order to ensure safe working and avoid glitches the following steps must be performed whenever any
updtate in the prescaling rate is desired:
1. Write 0 at GPREN bit in EMIOSMCR register, thus disabling global prescaler;
2. Write the desired value for prescaling rate at GPRE[0:7] bits in EMIOSMCR register;
3. Enable global prescaler by writing 1 at GPREN bit in EMIOSMCR register.
The prescaler is not disabled during either freeze state or negated GTBE input.
9.5.4.1 Effect of Freeze on the GCP
When the FRZ bit in the EMIOSMCR register is set and the module is in debug mode, the operation of
GCP submodule is not affected, i.e., there is no freeze function in this submodule.
Freescale Semiconductor
PXD10 Microcontroller Reference Manual, Rev. 1
Preliminary—Subject to Change Without Notice
9-45