programming pins MC9S12XS128

[alfonsovargashe]

good afternoon .. I need to know specifically what the programming pins MC9S12XS128 freescale microcontroller programmer ... and that we could use. We are working on a module microcontroller programming universal as thesis ... thanks for your quick help

[Monica]

Hola Alfonso!

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[RadekS · Accepted solution]

From datasheet: “The background debug module (BDM) sub-block is a single-wire, background debug system implemented in on-chip hardware for minimal CPU intervention. All interfacing with the BDM is done via the BKGD pin.”

So, for programming you will need MODC/BKGD pin and additionally also RESET pin.

Ground signal is self-evidence and some programming devices require also MCU power supply voltage (3.3V..5V).

The BKGD/MODC pin is used as a pseudo-open-drain pin. Therefore typically BDM interface drive this pin by open-drain output. In case of S12XS family, the BKGD pin has an internal pull-up device.

For onboard BDM connection is typically used 6pin BDM connector (2x3 pin header with pitch 2.54mm/100mils).

Please look at DEMO9S12XSFAME board schematic from attachment.