CDC3272G-C Micronas Intermetall GmbH, CDC3272G-C Datasheet - Page 21

• Manufacturer Part Number: CDC3272G-C
• Description: ARM7-Based Car Dashboard Controller
• Manufacturer: Micronas Intermetall GmbH

ADVANCE INFORMATION
6. Core Logic
6.1. Control Word (CW)
A number of important system configuration properties are
selectable during device start-up by means of a unique Con-
trol Word (CW).
6.1.1. Reset Active
At the end of the reset period, the device fetches this CW
from address locations 0x20 to 0x23 of a source that is
determined by the state of pins TEST and TEST2 and flag
MFPLR.MFPL, see Table 6–1 for MCM parts, Table 6–2 for
ROM parts.
Table 6–1: CW fetch in MCM parts (QFP128)
Table 6–3: Some common system configurations and the corresponding CW setting
Micronas
Control Word Fetch
desired from
Int. Flash
Int. Flash
Ext. via Multi Function port
Int. Special Function ROM
1)
MFPL = 0 set before
Part
Type
MCM
ROM
ROM
Only available after a non-Power-On RESET with
Program Start desired from
int. 16-Bit Flash (Am29LV400BT)
int. 32-Bit ROM, 16-Bit mode
int. 32-Bit ROM, 32-Bit mode
Necessary Reset con-
figuration
TEST2
0
0
1
TEST
0
1
x
April 30, 2003; 6251-615-1AI
MFPL
x
1
0
x
1)
Additional desired properties
-
-
-
As can be seen from Table 6–1, the device disables external
access (through the Multi Function port) to internal code, as
long as MFPLR.MFPL is 1 (= state after UVDD power-up).
Setting it to 0 requires internal SW. By this means, an effec-
tive device lock mechanism is implemented, that prevents
unauthorized access to internal SW.
In ROM parts, flag MFPLR.MFPL is available, but does not
lock the Multi Function port. Thus Table 6–1 reduces to Table
6–2.
Table 6–2: CW fetch in ROM parts (QFP128)
6.1.2. Reset Inactive
When exiting Reset, the CW is read and stored in the Control
Register (CR) and the system will start up according to the
configuration defined therein.
Normally the CW is fetched from the same memory that the
system will start executing code from. Table 6–3 gives fix
CWs for a list of the most commonly used configurations.
Control Word Fetch desired from
Internal ROM
External via Multi Function port
Int. Special Function ROM
Necessary CW
31:16
Don’t care
Don’t care
0xFFBA
CDC 3272G-C
Necessary Reset
config. of pins
TEST2
0
0
1
15:0
0x7F5F
0x7F5F
0x775F
TEST
0
1
x
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