MPC561MZP56 Freescale, MPC561MZP56 Datasheet - Page 356

• Manufacturer Part Number: MPC561MZP56
• Manufacturer: Freescale

Specifications of MPC561MZP56

• Cpu Family: MPC56x
• Device Core: PowerPC
• Device Core Size: 32b
• Frequency (max): 56MHz
• Interface Type: QSPI/SCI/SPI/UART
• Total Internal Ram Size: 32KB
• # I/os (max): 56
• Number Of Timers - General Purpose: 22
• Operating Supply Voltage (typ): 2.6/5V
• Operating Supply Voltage (max): 2.7/5.25V
• Operating Supply Voltage (min): 2.5/4.75V
• On-chip Adc: 2(32-chx10-bit)
• Instruction Set Architecture: RISC
• Operating Temp Range: -40C to 125C
• Operating Temperature Classification: Automotive
• Mounting: Surface Mount
• Pin Count: 388
• Package Type: BGA
• Program Memory Type: ROMLess
• Program Memory Size: Not Required
• Lead Free Status / RoHS Status: Not Compliant

External Bus Interface
memory to three-state the bus before the bus discharge is initiated. EHTR has a slight performance
reduction impact since it adds a clock gap between some read and write cycles.
9.5.3.1
Pre-discharge mode should be enabled in the following cases:
9.5.3.2
Systems that require pre-discharge operation should include the following steps:
9-16
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When external devices can charge the data bus to a higher voltage level than 3.1 volts
And when one or more of the following occurs:
— The MPC561/MPC563 uses write accesses to any external memory
— Data show cycles are enabled
— Instruction show cycles are enabled in code compression mode (MPC562/MPC564 only)
Execute boot sequence
Set EHTR bit in all relevant memory banks during the memory controller initialization phase
(configure ORx, and BRx) if it is required to extend the time between read cycles, and
pre-discharge phase of write cycles.
Set PREDIS_EN in PDMCR2 register
Start to write data to external devices
Operating Conditions
Initialization Sequence
EHTR also adds one idle clock for two consecutive read cycles from
different memory banks.
The pre-disharge will not occur, when using multiple processors with a
common bus accessing an external device, if the processor that initiates a
read is different from the processor that initiated the previous write. Perform
a write to the external device to discharge the external bus, or read a value
of 0x0 from the external device, prior to accessing another MCU on the
same bus.
In the case of code compression program tracking (3rd case above), the
PREDIS_EN bit should only be set when program tracking is not required
since pre-discharge mode overwrites the compression show cycles data. The
user should not set PREDIS_EN bit when program tracking is required on
development system, and set PREDIS_EN bit on the production version.
EHTR can always be set to keep the same system performance during
development, and production phases.
MPC561/MPC563 Reference Manual, Rev. 1.2
NOTE
NOTE
NOTE
Freescale Semiconductor