AN2667 Freescale Semiconductor / Motorola, AN2667 Datasheet - Page 13

• Manufacturer Part Number: AN2667
• Description: Multi-Controller Hardware Development for the MPC5xx Family
• Manufacturer: Freescale Semiconductor / Motorola

4.2
The MPC5xx that is configured to operate in peripheral mode does not handle interrupts
that are generated by its timers and peripherals. This task must be performed by a
device in master or slave mode. In order to do so, the pin SGPIOC7/IRQOUT/LWP0
must be configured as IRQOUT ( SIUMCR[GPC] = 11). In this way, any internal
interrupt request will assert this pin..
The pin SGPIOC7/IRQOUT/LWP0 must be connected to one of the interrupt request
inputs (IRQ[1:7]). IRQ0 should not be used as it is an NMI and will result in application
code jumping to 0x100(reset exception).
These pins may have another function due to pin multiplexing. It is the responsibility
of the user to program pin multiplexing correctly.
5 Switch Between Operation Modes
The user must be careful when switching between operation modes. Namely, when two
cores are active and the mode of one device is switched from slave to master, or slave
to peripheral A situation may arise where a slave device is performing some internal
accesses that have not yet completed. In this instance when the master tries to place
the slave device into peripheral, or master mode it may cause the external access to be
terminated by RETRY.
If the pin IRQ3/KR/RETRY/SGPIOC3 is not programmed to operate as retry in advance,
the system will hang.
6
The MPC5xx family consists of the MPC555 and MPC561-6 devices. The differences
between the MPC555 and MPC56x are minimal with regard to multi-controller
operation. The major difference is that the MPC555 cannot have its vector table
relocated to internal SRAM therefore application code cannot be executed from internal
RAM from reset.
The other difference is that the bus voltages are different, the MPC555 is 3.3V and the
MPC56x is 2.6V therefore it is recommended to use multiple controllers of either the
MPC555 or the MPC56x.
MOTOROLA
Interrupt Handling
MPC555/MPC56x Differences
Multi-Controller Hardware Development for the MPC5xx Family
Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
NOTE
NOTE
13 - 16