Chapter 3 Memory Mapping Control (S12ZMMCV1)
S12ZVHY/S12ZVHL Family Reference Manual Rev. 1.05
116
Freescale Semiconductor
3.1.1
Glossary
3.1.2
Overview
The S12ZMMC provides access to on-chip memories and peripherals for the S12ZCPU, the S12ZBDC,
and the ADC. It arbitrates memory accesses and determines all of the MCU memory maps. Furthermore,
the S12ZMMC is responsible for selecting the MCUs functional mode.
3.1.3
Features
•
S12ZMMC mode operation control
•
Memory mapping for S12ZCPU, S12ZBDC, and ADC
— Maps peripherals and memories into a 16 MByte address space for the S12ZCPU, the
S12ZBDC, and the ADC
— Handles simultaneous accesses to different on-chip resources (NVM, RAM, and peripherals)
•
Access violation detection and logging
— Triggers S12ZCPU machine exceptions upon detection of illegal memory accesses and
uncorrectable ECC errors
— Logs the state of the S12ZCPU and the cause of the access error
3.1.4
Modes of Operation
3.1.4.1
Chip configuration modes
The S12ZMMC determines the chip configuration mode of the device. It captures the state of the MODC
pin at reset and provides the ability to switch from special-single chip mode to normal single chip-mode.
Table 3-2. Glossary Of Terms
Term
Definition
MCU
Microcontroller Unit
CPU
S12Z Central Processing Unit
BDC
S12Z Background Debug Controller
ADC
Analog-to-Digital Converter
unmapped
address range
Address space that is not assigned to a memory
reserved address
range
Address space that is reserved for future use cases
illegal access
Memory access, that is not supported or prohibited by the S12ZMMC, e.g. a data store to NVM
access violation
Either an illegal access or an uncorrectable ECC error
byte
8-bit data
word
16-bit data
