System Integration Unit (SIU)
MPC5510 Microcontroller Family Reference Manual, Rev. 1
6-12
Freescale Semiconductor
Preliminary
6.3.2.2
Reset Status Register (SIU_RSR)
The SIU_RSR reflects the most recent source, or reset sources, and the pins’ configuration state at reset.
This register contains one bit for each reset source, indicating the last reset was power-on reset (POR),
external, software system, watchdog, loss of PLL lock, loss of clock or checkstop reset. A reset status bit
set to logic one indicates the reset type that occurred. After it is set, the reset source status bits in the
SIU_RSR remain set until another reset occurs. In the following cases more than one reset bit is set:
1. If a power-on reset request has negated and the device is still in the resulting reset, and then an
external reset is requested, both the power-on and external reset status bits will be set. In this case,
the device started the reset sequence due to a power-on reset request but ended the reset sequence
after an external reset request.
2. If any of the loss of clock, loss of lock, watchdog or checkstop reset requests occur on the same
clock cycle, and no other higher priority reset source is requesting reset (
), the reset status
bits for all of the requesting resets are set.
Simultaneous reset requests are prioritized. When reset requests of different priorities occur on the same
clock cycle, the lower priority reset request is ignored. Only the highest priority reset request's status bit is
set. Except for a power-on reset request and condition 1 above, all reset requests of any priority are ignored
until the device exits reset.
1
PKG default value reflects the device package type as defined in
MASKNUM_MAJOR default value is 0x0 for the device’s initial mask set and changes for each major mask set revision.
MASKNUM_MINOR default value is 0x0 for the device’s initial mask set and changes for each minor mask set revision.
Table 6-3. SIU_MIDR Field Descriptions
Field
Description
PARTNUM
MCU Part Number. Read-only, mask-programmed part identification number of the MCU. Reads
0x5516 for the MPC5516.
CSP
Chip Scale Package. The CSP bit indicates whether the die is mounted in a chip scale package.
0 Not a chip scale package.
1 Chip scale package.
PKG
Package Configuration. These values set the pin package used for each MPC5510 device.
01101 144-pin LQFP
10001 176-pin LQFP
10000 208-pin BGA
All other combinations are reserved
bits 22–23
Reserved
MASKNUM_MAJOR
Major Mask Revision Number. Read-only, mask-programmed mask number of the MCU. Reads
0x0 for the device’s initial mask set and changes for each major mask set revision.
MASKNUM_MINOR
Minor Mask Revision Number. Read-only, mask-programmed mask number of the MCU. Reads
0x0 for the device’s initial mask set and changes for each minor mask set.