CDC3205G-C Micronas, CDC3205G-C Datasheet - Page 58

• Manufacturer Part Number: CDC3205G-C
• Description: Automotive Controller Family The Device is a Microcontroller For Use in Automotive Applications.the On-chip Cpu is an Arm Processor ARM7TDMI with 32-bit Data And Address Bus, Which Supports Thumb format Instructions.
• Manufacturer: Micronas

CDC 32xxG-C
For special purposes, the CW source and the program
source may differ. For these purposes, a detailed description
6.2. Device Lock Module (DLM)
Together with the corresponding application software the
DLM allows to establish protections against unwanted device
accesses from outside the device and against unwanted
flash data erase. It is composed of the
- Multi Function Port Lock (MFPL), the
- Emu Bus Write Enable Control bit CR.EWE and the
- Special Function ROM (SFR) system.
6.2.1. Multi Function Port Lock (MFPL)
To protect the memories contents against access from out-
side the device, the Multi Function port, used as Test bus,
has to have a protection mechanism that is active by default.
Together with appropriate hardware the Multi Function Port
Lock (MFPL), controlled by a bit located in the Multi Function
Port Lock Register (MFPLR), ensures a disabled Multi Func-
tion port after POR (Power On RESET).
1)
MFPL
r/w1:
r/w0:
6.2.2. Emu Bus Write Enable (EWE)
In addition to MFPL, which protects the device memories
against accesses from outside, with Emu Bus Write Enable
(EWE) inactive, the Emu Bus is protected against write from
anywhere, external via Test Bus or internal via EMU or mem-
ory bus.
EWE is controlled by a bit in the Control Register which is
cleared (inactive) by RESET. It prevents unauthorized and
unintended Flash write and/or erase. EWE is located in the
CR to be set easily by the control word generation of the
emulation hardware. Code can be downloaded into the emu-
lation RAM without having to enter a dedicated register write
command or running a script file before. Write accesses by
the debugger, e.g. to set breakpoints, may take place imme-
diately after RESET.
For details on the Control Register please refer to chapter
“Control Register and Memory Interface”.
With MFPL and CR.JTAG the device can be protected
against external read and write accesses.
In addition, CR.EWE offers to lock the Emu Bus/Flash mem-
ory separately against external and internal write and erase.
56
r/w
Set by POR or wake-up from power saving modes.
MFPLR
x
x
7
x
x
6
Multi Function Port Lock
Locked
Not locked
Multi Function Port Lock Register
5
x
x
4
x
x
3
x
x
2
x
x
1
x
x
June 12, 2003; 6251-579-1PD
MFPL
1
0
1)
Res
Offs
of the CW and CR function is given in the chapter “Control
Register and Memory Interface”.
With the reset status of EWE = 0 there is no flash write possi-
ble at first. EWE = 1 has to be programmed by software
before.
Appropriate precautions within the application software are
necessary, especially controlling DMA and PATCH activities,
not to undermine a system lock.
6.2.3. Special Function ROM (SFR)
To get the CW from the Multi Function port, MFPL has to be
set to 0 before. This can be achieved either by a run through
an appropriate part of the Special Function ROM code or by
a corresponding application software that prepares MFPL =
0. The necessary RESET to follow must not be a POR,
because it resets MFPL to 1. Power saving modes also set
MFPL = 1.
For details on the SFR please refer to chapter “Memory and
Special Function ROM (SFR) System”.
PRELIMINARY DATA SHEET
Micronas