MPC561/MPC563 Reference Manual, Rev. 1.2
Freescale Semiconductor
7-1
Chapter 7
Reset
This section describes the MPC561/MPC563 reset sources, operation, control, and status.
7.1
Reset Operation
The MPC561/MPC563 has several inputs to the reset logic which include the following:
•
Power-on reset
•
External hard reset pin (HRESET)
•
External soft reset pin (SRESET)
•
Loss of PLL lock
•
On-chip clock switch
•
Software watchdog reset
•
Checkstop reset
•
Debug port hard reset
•
Debug port soft reset
•
JTAG reset
•
Illegal bit change (ILBC)
All of these reset sources are fed into the reset controller. The control logic determines the cause of the
reset, synchronizes it, and resets the appropriate logic modules, depending on the source of the reset. The
memory controller, system protection logic, interrupt controller, and parallel I/O pins are initialized only
on hard reset. External soft reset initializes internal logic while maintaining system configuration.
The reset status register (RSR) reflects the most recent source to cause a reset.
7.1.1
Power-On Reset
The power-on reset pin, PORESET, is an active low input. In a system with power-down low-power mode,
this pin should be activated only as a result of a voltage failure on the KAPWR pin. After detecting the
assertion of PORESET, the MPC561/MPC563 enters the power-on reset state. During this state the
MODCK[1:3] signals determine the oscillator frequency, PLL multiplication factor, and the PITRTCLK
and TMBCLK clock sources. In addition, the MPC561/MPC563 asserts the SRESET and HRESET pins
at the rising edge of PORESET.
The PORESET pin should be asserted for a minimum time of 100,000 of clock oscillator cycles after a
valid level has been reached on the KAPWR supply. After detecting the assertion of PORESET, the
MPC561/MPC563 remains in the power-on reset state until the last of the following two events occurs:
Summary of Contents for MPC561
Page 84: ...MPC561 MPC563 Reference Manual Rev 1 2 lxxxiv Freescale Semiconductor...
Page 144: ...Signal Descriptions MPC561 MPC563 Reference Manual Rev 1 2 2 46 Freescale Semiconductor...
Page 206: ...Central Processing Unit MPC561 MPC563 Reference Manual Rev 1 2 3 62 Freescale Semiconductor...
Page 302: ...Reset MPC561 MPC563 Reference Manual Rev 1 2 7 14 Freescale Semiconductor...
Page 854: ...Time Processor Unit 3 MPC561 MPC563 Reference Manual Rev 1 2 19 24 Freescale Semiconductor...
Page 968: ...Development Support MPC561 MPC563 Reference Manual Rev 1 2 23 54 Freescale Semiconductor...
Page 1144: ...Internal Memory Map MPC561 MPC563 Reference Manual Rev 1 2 B 34 Freescale Semiconductor...
Page 1212: ...TPU3 ROM Functions MPC561 MPC563 Reference Manual Rev 1 2 D 60 Freescale Semiconductor...
Page 1216: ...Memory Access Timing MPC561 MPC563 Reference Manual Rev 1 2 E 4 Freescale Semiconductor...