AN2866 Freescale Semiconductor / Motorola, AN2866 Datasheet - Page 22

• Manufacturer Part Number: AN2866
• Description: Migrating from the MC68332 to the ColdFire MCF523x
• Manufacturer: Freescale Semiconductor / Motorola

Device Differences
2.5.1
When the RCON pin is asserted at reset, the state of several of the device’s pins determines the mode of
operation for the device. If RCON is not asserted at reset, then the default configuration is used. This
section discusses the modes of operation and how the device is configured for the various modes.
For the MCF523x, there are four mode settings used to configure the device for a specific configuration.
These mode settings are boot data port size, output pad drive strength, chip clock mode, and chip select
configuration. Each of these mode parameters have two to four different selections:
Table 7
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Boot data port size
— 32-bit (default)
— 16-bit
— 8-bit
Output pad strength
— Partial drive strength (default)
— Full drive strength
Clock mode
— Normal PLL with external crystal (default)
— Normal PLL with external oscillator
— 1:1 PLL Mode
— External oscillator mode (no PLL)
Chip select configuration
— PADDR[7:5] configured as A[23:A21] (default)
— PADDR7 configured as CS6, PADDR[6:5] as A[22:A21]
— PADDR[7:6] configured as CS[6:5], PADDR5 as A21
— PADDR[7:5] configured as CS[6:4]
shows the data bus pins and the dedicated pins used by each device for chip configuration.
Chip Configuration
Migrating from the MC68332 to the ColdFire
®
MCF523x, Rev. 1.0
Freescale Semiconductor