Freescale Semiconductor TWR-K21D50M User guide

TWR-K21D50M Tower Module

User’s Manual

Rev. 1.01

TWR-K21D50M Tower Module User’s Manual Page 1 of 16

Table of Contents

1 TWR-K21D50M ........................................................................................................................................ 3

2 Contents ...................................................................................................................................................... 4

3 TWR-K21D50M Features ...................................................................................................................... 4

4 Get to Know the TWR-K21D50M ........................................................................................................ 5

5 Reference Documents ............................................................................................................................ 6

6 Hardware description ............................................................................................................................ 7

6.1 Block Diagram ...................................................................................................................................................................... 7

6.2 Microcontroller .................................................................................................................................................................... 8

6.3 Clocking ................................................................................................................................................................................ 10

6.4 System Power .................................................................................................................................................................... 10

6.5 Debug Interface ................................................................................................................................................................ 10

6.6 OSJTAG ................................................................................................................................................................................. 10

6.7 Accelerometer ................................................................................................................................................................... 11

6.8 Potentiometer, Pushbuttons, LEDs ........................................................................................................................... 11

6.9 General Purpose Tower Plug-in (TWRPI) Socket ............................................................................................... 12

6.10 USB ...................................................................................................................................................................................... 12

7 TWR-K21D50M Jumper Options and Headers ........................................................................... 13

8 Useful links ............................................................................................................................................. 15

TWR-K21D50M Tower Module User’s Manual Page 2 of 16

Controller Module

Secondary Elevator

Primary Elevator

•

Board Connectors

Peripheral Module

Tower Plug

-

In (TWRPI) Socket

1 TWR-K21D50M

The TWR-K21D50M microcontroller module is designed to work either in standalone mode or as part of the Freescale
Tower System, a modular development platform that enables rapid prototyping and tool re-use through
reconfigurable hardware. Take your design to the next level and begin constructing your Tower System today by
visiting www.freescale.com/tower for additional Tower System microcontroller modules and compatible peripherals.
For TWR-K21D50M-specific information and updates, visit www.freescale.com/TWR-K21D50M

• Tower MCU board

• Works stand-alone or in Tower System

• Features integrated debugging interface

for easy programming and run control
via standard USB cable

• Adds features and functionality

• Can accept TWRPIs such as sensors

and radios

• Additional and secondary serial and

expansion bus signals

• Standardized serial assignments

• Mounting holes and expansion

connectors for side-mounting
peripheral boards

• Common serial and expansion bus

signals

• Two 2x80 connectors for easy signal

access and side-mounting board

• Power regulation circuitry

• Standardized signal assignments

• Mounting holes

Approximately 3.5” H x 3.5” W x 3.5” D

when fully assembled

• Four card-edge connectors

• Uses PCI Express® connectors

(x16, 90 mm/3.5” long, 164 pin)

• Adds features and functionality

to your designs

• Interchangeable with other

peripheral modules and
compatible with other
controller/processor modules

• Examples include serial interface,

memory, Wi-Fi®, graphical LCD,
motor control, audio, Xtrinsic
sensing and high precision
analog modules

TWR-K21D50M Tower Module User’s Manual Page 3 of 16

Figure 1. Freescale Tower System Overview

2 Contents

The

TWR-K21D50M

• TWR-K21D50M board assembly

• 3 ft A to micro-B USB cable for debug interface and power or MK21DN512VMC5 USB interface

• CR2025 coin cell battery for VBAT power supply

• Quick Start Guide

3

TWR-K21D50M Features

• Tower-compatible microcontroller module

• MK21DN512VMC5 MCU (50 MHz, 512 KB Flash, 64 KB RAM, low power, 121 MAPBGA package)

• Dual-role USB interface with Micro-AB USB connector

• General-purpose Tower Plug-in (TWRPI) socket

• On-board debug circuit: MC9S08JM60 open source JTAG (OSJTAG) with virtual serial port

• Three-axis accelerometer (MMA8451Q)

• Four (4) user-controllable LEDs

• Two (2) user pushbutton switches for GPIO interrupts

• One (1) user pushbutton switch for MCU reset

• Potentiometer

• Independent, battery-operated power supply for Real Time Clock (RTC) and tamper detection modules

NOTE: The TWR-K21D50M contains some components that are reserved for future revisions of this board and are not
functional with the MK21DN512VMC5 MCU.

contents include:

TWR-K21D50M Tower Module User’s Manual Page 4 of 16

Power/OSJTAG

Board power selection

RESET

JTAG

selector

4 Get to Know the TWR-K21D50M

Micro-USB

Regulator option

K21 Micro-USB

VBAT options

JM60 BDM

JM60 Bootloader
Enable

General Purpose
TWRPI Plug-In

Potentiometer

LEDs

Accelerometer

Figure 2. Front side of TWR-K21D50M module

(TWRPI devices not shown)

TWR-K21D50M Tower Module User’s Manual Page 5 of 16

Tamper pins

SW2

SW3