project module


The above picture shows the MicroDragon project module which includes the 9s12 MCU, MC9S12DG256CPVE.  
The price also includes 4 of 14x2 male headers and 4 of 14x2 female receptacle sockets.

This module is basically an adapter that converts a surface mount device ( 112-pin MCU ) to a through hole device.  It's used as a core module in a HCS12 / 9S12 project.  It's designed to be used in senior projects made by students who already have some good experiences in the HCS12 / 9S12 family. This is not something for learning embedded programming.  If you should consider yourself a novice, we recommend you purchase the Dragon12 Plus2 instead.  


  • 16 MHz crystal, 8 MHz default bus speed and up to 25MHz bus speed via PLL
  • Pre-installed with Serial Monitor for CodeWarrior
  • 91 of MC9S12DG256 I/O pins are accessible on male header connectors for user applications 
  • On-board BDM-in connector to be connected with a BDM from multiple venders for debugging
  • Besides the on-chip 256K flash, 12K RAM and 4K EEPROM, the MC9S12DG256 MCU also includes the following on-chip peripherals:
    • 3 SPIs
    • 2 SCIs
    • 2 CANs
    • I2C interface
    • 8 16-bit timers
    • 8 PWMs
    • 16-channel 10-bit A/D converter
  • SCI0 header for connecting the SCI0 to a PC com port via Wytec's USB to TTL adapter
  • I/O pin layout is identical to MiniDragon+ and MiniDraon Plus2
  • Small PC board size 2.2" X 2.2"


Operating Instructions:

The circuitry of the MicroDragon module is very simple and you probably would know how to use it by reading schematics.

It provides a fast way to make your own HCS12 / 9S12 prototype board since you don't have to deal with any problems of soldering a 112-pin LQPF SMD chip. 

The kit comes with a set of four 14x2 male headers and a set of four 14x2 female connectors.  You will have to decide which set is going to be soldered on the module for your application.


The headers and their functions are listed below: 

J1 --- BDM input and is used by a BDM or a BDM POD for programming the on-chip flash memory or debugging code. 

J2 --- 5V VCC and GND. It can provide 5V for a target board or can be powered by an external regulated 5V,
  never place a jumper on J3
. In doing so you will make a short circuit on the module. 
  If you make a carrier board for supplying 5V to this module, the best way is to connect the external 5V to pin 41 (VDDR) and
  Ground to pin 40 (VSSR)

J3 --- SCI0 connector. It provides TX and RX of the SCI0 in TTL level.  

J4 --- It connects USB 5V to the VCC of the module. 
  When using 5V from USB port via a UTA, you need to place a jumper on J4.
  If you supply an external 5V to the MicroDragon module via J2, then remove the jumper on J4.

J5 --- For selecting RUN or LOAD mode.
  The jumper is not installed when download or debug code using code Warrior IDE.
  To run your code, you need to place a jumper on J5

J6 --- PAD0, it's located on solder side

J7 --- PAD1, it's located on solder side.  When it's pre-installed with D-Bug12 monitor, you can short J6 and J7 to ground to enable
  D-Bug12 monitor.


Three ways to power up  the module:

  1. Remove the jumper on J4, and connect an external regulated 5V DC to J2, the LED indicator should blink at least twice.

  2. Remove the jumper on J2 and place a jumper on J4, connect a UTA adapter to J3, the USB port on laptop will provide 5V to the module and the LED indicator should blink at least twice.

  3. Remove the jumpers on J2 and J4, connect a BDM or a BDM POD to J1. The BDM or BDM POD will provide 5V to the module and the LED indicator should blink at least twice.

    If Freescale serial monitor or bootloader+D-Bug12 monitor is not installed or erased by a BDM, the LED indicator will not blink during power up or reset.


Three ways to develop code using the MicroDragon:

  1. In the stand-alone configuration, the MicroDragon can be pre-installed with serial monitor (at default) or D-Bug12 monitor (per customer's request), but it requires a UTA adapter to interface with a PC.

    If the MicroDragon is pre-installed with serial monitor and a test program at factory, the state of the J5 is tested by the serial monitor for selecting RUN or LOAD mode during power up or reset, and the LED indicator will blink twice to indicate that the serial monitor is functioning. If there is a jumper on J5 the monitor will wait for a command from PC. If there is no jumper placed on J5 the LEDs will flash 2 more times to indicate that the program execution is diverted to user code.  When the user code ( the pre-loaded factory test program) is running the LED indicator will flash rapidly.

    The serial monitor works with Code Warrior IDE.  For more information about Code Warrior please visit:  http://www.evbplus.com/Code_Warrior_hcs12.html

    Per customer's request it can be pre-installed with D-Bug12 monitor. Both the J6 and J7 on the solder side are replaced by a 10K resistor so both the PAD0 and PAD1 are low and will run D-Bug12 monitor. For operating all 4 modes, you need to change the states of the PAD0 and PAD1 by connecting one of them, or both to VCC.

  2. Another approach is to use your TinyBDM, or MiniDragon or Dragon12 plus as a BDM POD and debug the MicroDragon via BDM connection, so you don't need to buy a UTA.

    In this setup, you are going to use D-Bug12 monitor to debug your code and the D-Bug12 monitor is located in the BDM POD, all flash memory of the chip can be used for user programs.

  3. The last approach is to purchase the Multilink, a USB based BDM, from P & E Microsystems. It will cost you $99, but it offers more features.

Soldering tips:

  1. You should use a non-clean type solder when soldering the male headers or female sockets. The residual of non-clean solder flux won't be washed away by water, but will not harm the board if it's left on the module. If you would like to clean your module after soldering, you can use alcohol to clean up residue and use a air compressor or even a hair dryer to blow away excess alcohol.

  2. If you use a water soluble type solder, you need to wash your module in warm water ASAP after soldering. If solder residue is left on the module too long it will cause corrosion on the module. If it's not washed thoroughly, any small amount of residues will also cause corrosion on the module in the future.

Product Code Price (USD) Description




The price includes the MicroDragon module and four of 14x2 male headers and four of 14x2 female receptacle sockets to be used in a user application target board.

MC9S12 / 9s12 project module

Educational discount price for schools, students and hobbyists

UTA $14 The price includes the USB to TTL Breakout module, an 4x2 IDC cable.