TWR-KL25Z Tower Module
User Guide
TWR-KL25Z
The TWR-KL25Z microcontroller module works either in standalone mode or as part of the NXP 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 http://www.nxp.com/tower for additional Tower System microcontroller modules and compatible peripherals.
For TWR-KL25Z, specific information, and updates visit http://www.nxp.com/TWR-KL25Z48M. 
Contents
The TWR-KL25Z contents include:
- TWR-KL25Z board assembly
- 3ft A to mini-B USB cable for debug interface and power
- Quick Start Guide
TWR-KL25Z Features
- Tower-compatible microcontroller module
- MKL25Z128VLK4 MCU (48 MHz, 128KB Flash, 16 KB RAM, Low power, 80LQFP package
- Dual-role USB interface with Micro-AB USB connector
- Touch Tower Plug-in Socket
- General purpose Tower Plug-in (TWRPI) socket
- On-board debug circuit MK20 OpenSDA serial debug interface with virtual serial port and mass storage device bootloader
- Three-axis accelerometer (MMA8451Q)
- Four (4) user-controllable LEDs
- Two (2) capacitive touch pads
- Two (2) user pushbutton switches
- Infrared transmit and receive
- Potentiometer for ADC measurements
- GPIO header for prototyping
Get to Know the TWR-KL25Z
Reference Documents
The documents listed below provide more information on the Kinetis family, Tower System, and MCU Modules. The following documents are available here: http://www.nxp.com/TWR-KL25Z48M or http://www.nxp.com/kinetis.
- TWRKL25ZQSG: Quick Start Guide
- TWR-KL25Z-SCH: Schematics
- TWR-KL25Z-PWA: Design Package
- MKL25Z128VLK4 Reference Manual
- Tower Configuration Tool
- Tower Mechanical Drawing
Hardware Description
The TWR-KL25Z is a Tower MCU Module featuring the MKL25Z128VLK4 —a Kinetis microcontroller with USB 2.0 full-speed OTG controllers in an 80 LQFP package. TWR-KL25Z is used in the NXP Tower System but can operate stand-alone. An on-board debug circuit, OpenSDA, provides an SWD interface and a power supply input through a single USB mini-AB connector, as well as a serial to USB, CDC class compliant UART interface.
6.1. Block diagram
6.2. Microcontroller
The TWR-KL25Z features the MKL25Z128VLK4. This 48 MHz microcontroller is part of the Kinetis L series and is available in an 80 LQFP package. The following table notes the features of MKL25Z128VLK4.
Table 1. Features of MKL25Z128VLK4
|
Feature |
Description |
| Ultra-low power | 10 low-power modes with power and clock gating for optimal peripheral activity and recovery times. Stop currents of <150 nA (VLLS0), run currents of <130 uA/MHz, 4 µs wake up from Stop mode. Full memory and analog operation down to 1.71V for extended battery life. Low-leakage wake-up unit with up to eight internal modules and sixteen pins as wake-up. Sources in low-leakage stop (LLS)/very low-leakage stop (VLLS) modes. Low-power timer for continual system operation in reduced power states. |
| Flash and SRAM | 32 KB – 128 KB flash featuring fast access times, high reliability, and four levels of security protection. 4KB – 16 KB of SRAM. No user or system intervention to complete programming and erase functions and full operation down to 1.71V. |
| Mixed-signal | High-speed 16-bit ADC with configurable resolution. |
| capability | Single or differential modes for improved noise rejection. Analog comparator with 6-bit DAC reference. 12-bit independent DAC. |
| Performance | 48 MHz ARM Cortex-M0+ core. Up to four channel DMA for peripheral and memory servicing with reduced CPU loading and faster system throughput. Cross bar switch enables concurrent multi-master bus accesses, increasing bus bandwidth. Bit manipulation engine (BME) allows execution of single-instruction atomic bit-modify-write operations on the peripheral address space. |
| Timing and Control | Low power timers. A two-channel 32-bit periodic interrupt timer provides a time base for the RTOS task scheduler or trigger source for ADC conversion. |
| Human-Machine | Hardware touch-sensing interface (TSI) with up to 16 inputs. |
| Interface | TSI operates in low power modes (minimum current adder when enabled). TSI hardware implementation avoids software-polling methods. High sensitivity level allows use of overlay surfaces up to 5 mm thick. |
| Connectivity and | Full-Speed USB Device/Host/On-The-Go with device charge detect capability. |
| Communications | Optimized charging current/time for portable USB devices, enabling longer battery life. USB low-voltage regulator supplies up to 120 mA off-chip at 3.3 volts to power external components from 5-volt input. Three UARTs (one low-power UART module that retains functionality in stop modes and two UART modules). One Inter-IC Sound (I2S) serial interface for audio system interfacing. Two SPI modules and two I2C modules. |
| Reliability, Safety and | Independent-clocked computer operating properly (COP) guards against clock skew or code |
| Security | runaway for fail-safe applications such as the IEC 60730 safety standard for household appliances. |
6.3. Clocking
The Kinetis MCUs start up from an internal digitally controlled oscillator (DCO). The software can enable the main external oscillator (EXTAL0/XTAL0) if desired. The external oscillator/resonator can range from 32.768 kHz up to 32 MHz. An 8 MHz crystal is the default external source for the MCG oscillator inputs (XTAL/EXTAL).
A 32.768 kHz oscillator connects to the RTC_CLKIN pin by default.
6.4. System Power
When installed into a Tower System, the TWR-KL25Z powers either from an on-board source or from another source in the assembled Tower System.
In stand-alone operation, the main power source (5.0V) for the TWR-KL25Z module derives from either the OpenSDA USB mini-B connector or the MKL25Z128VLK4 USB micro-AB connector (J31). Two low-dropout regulators provide 3.3V and 1.8V supplies from the 5.0V input voltage.
Additionally, the 3.3V regulator built into the MKL25Z128VLK4 is selected to power the 3.3V bus. All the user-selectable options can be configured using two headers, J3 and J8.
6.5. Real Time Clock (RTC)
Y500 is a 32.768 kHz clock connected to RTC_CLKIN. By enabling the external clock option in the RTC, it is used as a highly precise time reference.
6.6. Debug Interface
There are two debug interface options provided: the onboard OpenSDA circuit and an external ARM SWD connector.
OpenSDA
An on-board MK20-OpenSDA circuit provides an SWD debug interface to the KL25Z128. A standard USB A male to mini-B male cable (provided) is used for debugging via the USB connector, J22. The OpenSDA interface also provides a USB-to-serial bridge.
Cortex Debug SWD Connector
The Cortex Debug SWD connector is a standard 2×5-pin (0.05″) connector providing an external debugger cable with access to the SWD interface of the KL25Z128.
| Pin | Function | TWR-KL25Z Connection |
| 1 | VTref | 3.3V MCU supply (V_BRD) |
| 2 | STUDIO | PTA3/TSI0_CH4/I2C1_SCL/FTM0_CH0/SWD_DIO |
| 3 | GND | GND |
| 4 | SWCLK | PTA0/TSI0_CH1/FTM0_CH5/SWD_CLK |
| 5 | GND | GND |
| 6 | NC | NC |
| 7 | NC | NC |
| 8 | NC | NC |
| 9 | NC | NC |
| 10 | RESET | RESET_b |
6.7. Infrared Port
An infrared transmit and receives interface is implemented as shown in Figure 5. The UART2_TX pin directly drives an infrared diode. The receiver uses an infrared phototransistor connected to UART2_RX through a low-pass filter. Internal to the K20D50M device, the output of the analog comparator is routed to a UART module for easier processing of the incoming IrDA data stream.
6.8. Accelerometer
An MMA8451Q digital accelerometer is connected to the KL25Z128 MCU through the I2C module, I2C1, and GPIO/IRQ signals, PTC5 and PTC6. The MMA8451Q is a smart low-power, three-axis capacitive micromachined accelerometer with 14 bits of resolution. The device is configured to generate inertial wake-up interrupt signals from any combination of the configurable embedded functions allowing the MMA8451Q to monitor events and remain in a low-power mode during periods of inactivity. For more information on the MMA8451Q, please visit the MMA8451Q Product Summary Page.
6.9. General-Purpose Tower Plug-in (TWRPI) Socket
The TWR-KL25Z features a socket (J4 and J5) that can accept a variety of different Tower Plug-in modules featuring sensors, RF transceivers, and more. The General Purpose TWRPI socket provides access to I2C, SPI, IRQs, GPIOs, timers, analog conversion signals, TWRPI ID signals, reset, and voltage supplies. The pinout for the TWRPI Socket is defined in Table 3.
Table 3. General Purpose TWRPI socket pinout
|
J4 |
J5 |
||
|
Pin |
Description | Pin |
Description |
| 1 | 5V VCC | 1 | GND |
| 2 | 3.3 V VCC | 2 | GND |
| 3 | GND | 3 | I2C: SCL |
| 4 | 3.3V VDDA | 4 | I2C: SDA |
| 5 | VSS (Analog GND) | 5 | GND |
| 6 | VSS (Analog GND) | 6 | GND |
| 7 | VSS (Analog GND) | 7 | GND |
| 8 | ADC: Analog 0 | 8 | GND |
| 9 | ADC: Analog 1 | 9 | SPI: MISO |
| 10 | VSS (Analog GND) | 10 | SPI: MOSI |
| 11 | VSS (Analog GND) | 11 | SPI: SS |
| 12 | ADC: Analog 2 | 12 | SPI: CLK |
| 13 | VSS (Analog GND) | 13 | GND |
| 14 | VSS (Analog GND) | 14 | GND |
| 15 | GND | 15 | GPIO: GPIO0/IRQ |
| 16 | GND | 16 | GPIO: GPIO1/IRQ |
| 17 | ADC: TWRPI ID 0 | 17 | UART0_RX / GPIO: GPIO2 |
| 18 | ADC: TWRPI ID 1 | 18 | GPIO: GPIO3 |
| 19 | GND | 19 | GPIO: GPIO4/Timer |
| 20 | Reset | 20 | UART0_TX / GPIO: GPIO5 |
6.10. Potentiometer, Pushbuttons, LEDs
The TWR-KL25Z features two pushbutton switches connected to GPIO/interrupt signals, one pushbutton connected to the master reset signal, two capacitive touchpad electrodes, four user-controllable LEDs, and a potentiometer connected to an ADC input signal. Refer to Table 6 “Connectors and Pin Usage” for information about which pins are connected to these features.
6.11. Touch Interface
The touch sensing input (TSI) module of the KL25Z128 MCU provides capacitive touch sensing detection with high sensitivity and enhanced robustness. Each TSI pin implements the capacitive measurement of an electrode.
The TWR-KL25Z provides two methods for evaluating the TSI module. There are two electrode- boards. Additionally, 12 TSI signals are connected to a Touch Tower Plug-in (TWRPI) socket (J2) that can accept Touch TWRPI daughter cards that may feature keypads, rotary dials, sliders, etc.
Table 4. Touch TWRPI socket pinout
|
Pin |
Description |
| 1 | P5V_TRG_USB |
| 2 | V_BRD |
| 3 | TSI0_CH9 |
| 4 | 3.3V VDDA |
| 5 | TSI0_CH10 |
| 6 | VSS (Analog GND) |
| 7 | TSI0_CH11 |
| 8 | TSI0_CH12 |
| 9 | TSI0_CH13 |
| 10 | TSI0_CH0 |
| 11 | TSI0_CH6 |
| 12 | TSI0_CH7 |
| 13 | TSI0_CH8 |
| 14 | TSI0_CH1 |
| 15 | TSI0_CH4 |
| 16 | TSI0_CH3 |
| 17 | ADC: TWRPI ID 0 |
| 18 | ADC: TWRPI ID 1 |
| 19 | GND |
| 20 | Reset |
USB
The KL25Z128 features a full-speed/low-speed USB module with OTG/Host/Device capability and a built-in transceiver. The TWR-KL25Z routes the USB D+ and D- signals from the KL25Z128 MCU directly to the on-board USB connector (J13)
A power supply switch with an enable input signal and the over-current flag output signal is used to supply power to the USB connector when the KL25Z128 is operating in host mode.
TWR-KL25Z Jumper Options
The following is a list of all the jumper options. The default installed jumper settings are shown in bold.
NOTE
Default Configuration: the board is powered by OpenSDA USB and RTC is powered by V_BRD.
| Jumper | Jumper designator | Signal | Jumper Option |
| V BRD | J7 | V_BRD | DEF: 1-2 VBRD to MCU PWR |
| J9 | VDDA_HDR | DEF: 1-2 VDDA to MCU PWR | |
| VREG IN SELECTOR |
J8 | VREG IN SELECTOR | DEF: 1-2 Regulator powered by OpenSDA USB 2-3 Regulator powered by tower elevator power |
| BOARD POWER SELECTION |
J3 | BOARD POWER SELECTION |
DEF: 1-3 P3.3V_REG powers V_BRD(MCU_PWR) 3-5 1.8V powers VBRD (MCU & Interface circuit input power) |
Table 6. Connectors and Pin Usage
| Module | Board Designator | Name | Options | Signal |
| USB | J6 | KL25 VOUT33 | DEF: OPEN | MCU PWR |
| J18 | KL25 USB VIRGIN | DEF: OPEN | P5V VIRGIN K25 | |
| J20 | KL25 USB ENA | DEF: OPEN | PTB11/SPI1 SCK | |
| J21 | KL25 USB FLAG | DEF: OPEN | PTE31/FTMO_CH4 | |
| IRDA | SW1 6-3 | IRAJ | OPEN | PTE22/ADCO DP3/ADCO SE3/U ART2_TX |
| SW1 5-4 | CMPO INFO | OPEN | PTE23/ADCO_DM3/ADCO_SE7A/ UART2 RX |
|
| Potentiometer | J1 | POT 5K | DEF: 1-2 | PTE29/ADCO_SE4B |
| Accelerometer | J24 | SDA Accelerometer Enable | DEF: 1-2 | PTC11/I2C1 SDA |
| J23 | SCL Accelerometer Enable | DEF: 1-2 | PTC10/I2C1 SCL | |
| J14 | ACCELEROMETER INT1 | DEF: OPEN | PTC5/LLWU P9/SPIO SCK/CMP —0 OUT |
|
| J15 | ACCELEROMETER INT2 | DEF: OPEN | PTC6/LLWU P10/EXTRG IN/SPI -0 MISO |
|
| GPIO Header | J11-1 | PTE20/ADCO DPO/ADCO S E0 |
||
| J11-2 | PTE21/ADCO DMO/ADCO SE-4A _ |
|||
| J11-3 | PTA1/TSIO CH2/UARTO R X |
|||
| J11-4 | GND | |||
| J11-5 | SWD DIO TGTMCU | |||
| J11-6 | PTE31/FTMO CH4 | |||
| J11-7 | PTB9 | |||
| J11-8 | PTA2/TSIO CH3/UARTO T X |
|||
| J11-9 | PTB11/SPI1 SCK | |||
| J11-11 | PTB10/SPI1 PCSO | |||
| J11-12 | GND | |||
| J11-13 | PTC4/LLWU P8/UART1 TX /FTNIO CH3 |
|||
| J11-14 | PTC3/LLWU_P7/UART1_R X/FTMO CH2/CLKOUT |
|||
| J11-15 | PTC12/FTM_CLKINO | |||
| J11-16 | PTC6/LLWU P10/EXTRG I N/SPI0 MISO |
|||
| J11-17 | PTC16 | |||
| J11-18 | PTC13/FTM_CLKIN1 | |||
| J11-19 | GND |
| Module | Board Designator | Name | Options | Signal |
| J11-20 | PTC17 | |||
| LEDs | J19 | LED orange Enable | DEF: 1-2 | PTA5/FTMO_CH2 |
| J22 | LED Yellow Enable | DEF: 1-2 | PTA16 | |
| SW1 8-1 | LED Green Enable | OPEN | PTA17 | |
| SW1 7-2 | LED Red Enable | OPEN | PTB8/EXTRG_IN | |
| Push Buttons | SW3 | SW3 | PTA4 | PTA4 |
| SW4 | SW4 | PTC3 | PTC3/LLWU_P7/UART1_RX/FTM O_CH2/CLKOUT |
|
| TSI Electrodes | Elec1 | Electrode) | TSIO_CH9 | PTB16/TSIO_CH9/UARTO_RX |
| Elec2 | Electrode2 | TSIO_CH10 | PTB17/TSIO_CH10 | |
| UART | J24 | KL25 UART RX (OpenSDA or Elevator) |
DEF: 2-3 | UART1_RX_TGTMCU |
| J26 | KL25 UART TX (OpenSDA or Elevator) |
DEF: 2-3 | UART1_TX_TGTMCU |
Useful Links
- http://www.nxp.com/TWR-KL25Z48M
- www.nxp.com
- www.iar.com/nxp
- www.pemicro.com
- www.nxp.com/codewarrior
o CodeWarrior MCUv10.3 and above - www.segger.com
o http://www.segger.com/jlink-flash-download.htm
Revision History
Table 7. Sample revision history
| Revision number | Date | Substantive changes |
| 1.0 | July-12 | Initial release |
| 1.0.1 | September-12 | First version. Updated to board rev C. |
| 1. | September-16 | Updated the contents section, web links and general information corrections. |
How to Reach Us:
Home Page:
nxp.com
Web Support:
nxp.com/support
Information in this document is provided solely to enable system and software implementers to use NXP products. There are no express or implied copyright licenses granted hereunder to design or fabricate any integrated circuits based on the information in this document. NXP reserves the right to make changes without further notice to any products herein.
NXP makes no warranty, representation, or guarantee regarding the suitability of its products for any particular purpose, nor does NXP assume any liability arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation consequential or incidental damages. “Typical” parameters that may be provided in NXP data sheets and/or specifications can and do vary in different applications, and actual performance may vary over time. All operating parameters, including “typicals,” must be validated for each customer application by the customer’s technical experts. NXP does not convey any license under its patent rights nor the rights of others. NXP sells products pursuant to standard terms and conditions of sale, which can be found at the following address:
nxp.com/SalesTermsandConditions.
NXP, the NXP logo, NXP SECURE CONNECTIONS FOR A SMARTER WORLD, Freescale, the Freescale logo, CodeWarrior, Energy Efficient Solutions logo, Kinetis, and Tower are trademarks of NXP B.V. All other product or service names are the property of their respective owners.
ARM, the ARM logo, and Cortex are registered trademarks of ARM Limited (or its subsidiaries) in the EU and/or elsewhere.
© 2016 NXP B.V.
Document Number: TWR-KL25Z-UM
Rev. 1.1
09/2016
Documents / Resources
 |
NXP TWR-KL25Z Tower Module [pdf] User Guide TWR-KL25Z, Tower Module, TWR-KL25Z Tower Module, Module |
