CMD-5xx 08/07/02
11
Option Switches and Jumpers
Mode Switch 1-4 External Reset Configuration Options
Mode Switches 1, 2, 3
and
4
configure the external Hard Reset Configuration Word when enabled. These switches provide a logic 0
or low level when off and a logic 1 or high level when on. The configuration is only presented to the data bus during Hard Reset if
External Configuration is enabled with the CFG_EN option jumper installed
and
the External Configuration switch enabled on the
PM-5xx module. The Hard Reset Configuration Word options are all defaulted to logic 0 when the Mode Switches are in the OFF
position. For more information on the MPC5xx Reset Configuration refer to the Reset Chapter in the respective MPC5xx technical
manual. The following tables represent common configuration items and should be verified against the MPC5xx installed.
Mode Switch 1
Control
Register Bit
Reset Function
Default Position
1
EARB
Internal or External Arbitration
Off = Internal
2
MSR[IP]
Initial Interrupt Prefix
Off = 0
3
BDRV
Bus Pin Drive Strength
Off = Full Drive
4
BDIS
Memory Controller Disable
Off = Enabled
5, 6
BPS
Boot Port Size: Off/Off = 32Bit Port, Off/On = 8 Bit Port
On/Off = 16 Bit Port
7
Reserved
Future Use
Off
8
Reserved
Future Use
Off
Mode Switch 2
Control
Register Bit
Reset Function
Default Position
1
Reserved
Future Use
2, 3
DBGC[0:1]
Debug Pins Configuration
Off = VFLS[0:1], BR, BG, BB, BI
4
DBPC
Debug Port Pins Configuration
Off = DSCK, DSDO, DSDI
5
ATWC
Address Type / Write Enable Pins Configuration
Off = WE/BE[0:3]
6, 7
EBDF
External Bus Division Factor
Off = Equal to CLKOUT
8
Reserved
Future Use
Off
Mode Switch 3
Control
Register Bit
Reset Function
Default Position
1
PRPM
Peripheral Mode Enable
Off = Not Peripheral
2,3
SC[0:1]
Single Chip Select, Off/On = 16 bit bus, On/Off = Single-chip w/ Show
cycles, On/On = Single-Chip
Off/Off = 32 bit bus
4
ETRC
Exception Table Relocation
Off = Disabled
5
FLEN
Internal CMFI Flash enable
On = Enabled
6
EN_COMP
Enable Code Compression ** Must be supported by processor.
Off = No compression
7
EXC_COMP
Enable Exception Compression *** Must be supported by processor
Off = No compression
8
Reserved
Future Use
Off
Mode Switch 4
Control
Register Bit
Reset Function
Default Position
1, 2
OERC
Other Exception Relocation Control ** ERTC on for any effect
Off , Off = 0x00 offset
3
Reserved
Future Use
Off
4
Reserved
Future Use
Off
5, 6, 7
ISB
Internal Space Base Select
Off, Off, Off = 0x00000000
8
DME
Dual Mapping Enable
Off = No Dual Mapping
CFG_EN Jumper
Enables/Disables External Reset Configuration drivers on the CMD5xx board. When installed, this jumper will connect the
EXCNF* signal from the PM-5xx module to the External Reset Configuration Word buffers and allow the Configuration word to be
driven onto the data bus during SRESET Condition. Removing this jumper will disable the Reset Configuration Word from being
driven on to the data bus. The jumper should be installed until the internal Hard Reset Configuration Word is programmed into the
MPC5xx internal flash memory of the microcontroller operating the board. This can be done from the utilities supplied with the
board in U15/U16.
