User`s manual
3.1.2 Jump-to-EEPROM mode: PAD1=0, PAD0=1
This mode enables the MC9S12DG256 to jump directly to the internal EEPROM at
location $0400 upon reset.
This mode makes the MC9S12DG256 a replacement for the old 68HC811E2
microcontroller, but it also gives you 3K EEPROM instead of 2K EEPROM with the
68HC811E2. The bus speed is 8MHz, one half of the crystal frequency by default, the
PLL function must be initialized by user’s code for a higher bus speed, because the D-
Bug12 monitor firmware that boosts bus speed to 24 MHz is bypassed. If you need to
auto start your code upon reset, the procedure is available in the folder named
eeprom_programming.
After booting up in this mode, the LCD should display the following message:
“MiniD-P3”
“ J-E ”
3.1.3 BDM POD mode: PAD1=1, PAD0=0
Warning: Because there is no room on the P3 board for the BDM out header so this
mode is not available for the P3 board. The function description is included here is
for reference only.
In this BDM POD mode, the D-Bug12 firmware acts as a master to access all target MCU
resources on the target board (another MiniDragon-Plus3 board) via the BDM port in a
non-intrusive manner. It becomes a BDM that will have all the features that a standard
BDM has in debugging the target MCU. Also, it gains all the features a programmer has
for programming the flash memory of the MCU on the target board (another MiniDragon-
Plus3 board).
To use the master board as a programmer, you need a 6-pin ribbon cable to connect from
the BDM OUT of the master board to the BDM IN of the target board (make sure that the
orientation of the cable is correct). You don’t have to provide the power to both boards, but
only to one board. The master board communicates to a PC COM port while the target
board does not need to be connected to a PC COM port.
After booting up in this mode, the LCD should display one of the following two messages:
If the D-Bug12 monitor is erased, the LCD will display the following message after reset:
“MiniD-P3”
“ P-E”
otherwise it will display:
“MiniD-P3”
“ BDM POD ”
and you should see the following message on PC screen:
Can't Communicate With Target CPU
1.) Set Target Speed (48000 KHz)
2.) Reset Target
3.) Reattempt Communication
4.) Erase & Unsecure
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