AN2866 Freescale Semiconductor / Motorola, AN2866 Datasheet - Page 23

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

Chip configuration is performed at reset, and reset out (RSTOUT) can be used to gate an external latch to
provide the desired polarity on each of the pins during chip configuration. The recommended chip
configuration circuit is shown in
Freescale Semiconductor
RCON
D26, D17,
D16
D20, D19
D21
CLKMOD1,
CLKMOD0
D25, D24
MCF523x
Pin
Chip
configuration
enable
Select chip
operating
mode
Select boot
data port size
Select output
pad drive
strength
Select clock
mode
Select chip
select /
address line
Configuration
Function
Chip
Table 7. MC68332/MCF523x Configuration Pin Descriptions
Migrating from the MC68332 to the ColdFire
0 Enabled
1 Disabled
111 Master
All other settings are reserved
00 32-bit port
10 8-bit port
01 16-bit port
11 32-bit port
0 Partial
1 Full
00 External clock mode (no PLL)
01 1:1 PLL mode
10 Normal PLL with external clock reference
11 Normal PLL with crystal reference
00 PADDR[7:5] configured as A[23:A21] (default)
10 PADDR7 configured as CS6, PADDR[6:5] as A[22:A21]
01 PADDR[7:6] configured as CS[6:5], PADDR5 as A21
11 PADDR[7:5] configured as CS[6:4]
Figure
4.
Pin State/Meaning
®
MCF523x, Rev. 1.0
Active low: if asserted,
then all configuration pins
must be driven
appropriately for desired
operation
V
a PLL mode is selected
DDPLL
Comments
must be supplied if
Device Differences
23