Freescale Semiconductor K20D72M User manual

Freescale Semiconductor Inc.
TWR-K20D72M
User Manual
Rev. 1.1

TWR-K20D72M User’s Manual Page 2 of 17
Contents
1 TWR-K20D72M Overview ......................................................................................................................4
1.1 Features..................................................................................................................................................................................4
1.2 Getting started .....................................................................................................................................................................5
1.3 Reference Documents.......................................................................................................................................................5
2 Hardware Description.............................................................................................................................5
2.1 K20D72M Microcontroller..............................................................................................................................................6
2.2 Clocking ..................................................................................................................................................................................7
2.3 System Power.......................................................................................................................................................................7
2.3.1 Board Power Select ...........................................................................................................................................................................7
2.3.2 RTC VBAT ..............................................................................................................................................................................................7
2.4 Debug Interface ...................................................................................................................................................................8
2.4.1 OSJTAG ....................................................................................................................................................................................................8
2.4.2 Cortex Debug Connector .................................................................................................................................................................8
2.5 USB Interface........................................................................................................................................................................9
2.6 Infrared Port.........................................................................................................................................................................9
2.7 External Bus Interface – FlexBus..................................................................................................................................9
2.8 Accelerometer......................................................................................................................................................................9
2.9 Potentiometer, Pushbuttons, LEDs .............................................................................................................................9
2.10 General Purpose Tower Plug-in (TWRPI) Socket............................................................................................ 10
2.11 Touch Interface.............................................................................................................................................................. 10
2.12 Microphone and buzzer.............................................................................................................................................. 11
3 Jumper Table ........................................................................................................................................... 12
4 Input/Output Connectors and Pin Usage Table........................................................................... 13
5 Elevator Connections ............................................................................................................................ 15

TWR-K20D72M User’s Manual Page 3 of 17
List of Figures
Figure 1. Front side of TWR-K20D72M module.......................................................................................... 4
Figure 2. Back side of TWR-K20D72M module........................................................................................... 5
Figure 3.TWR-K20D72M Block Diagram .................................................................................................... 6
Figure 4. Infrared Port Implementation ..................................................................................................... 9
List of Tables
Table 1. Cortex Debug Connector Pinout................................................................................................... 8
Table 2. TWRPI Socket Pin Description..................................................................................................... 10
Table 3. Touch TWRPI Pin Description ..................................................................................................... 11
Table 4. TWR-K20D72M Jumper Table..................................................................................................... 12
Table 5. I/O Connectors and Pin Usage Table .......................................................................................... 13
Table 6. TWR-K20D72M Primary Connector Pinout................................................................................. 15
Revision History
Revision Date Changes
0.1 March 15, 2011 Initial Release

TWR-K20D72M User’s Manual Page 4 of 17
1TWR-K20D72M Overview
The K20D72M Tower MCU Module (TWR-K20D72M) is a low-cost evaluation, demonstration and
development board, which features the Kinetis K20 72MHz low-power microcontroller. These devices
are based on the ARM® Cortex™-M4 architecture with USB 2.0 full-speed OTG controller. The TWR-
K20D72M microcontroller module can operate in stand-alone 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.
1.1 Features
The following list summarizes the features of the K20D72M Tower MCU boards:
•Tower compatible processor board
•S08JM60 based Open Source BDM (OSBDM) circuit
•Four (4) user-controlled status LEDs
•Two (2) Capacitive Touch Pads and two (2) mechanical push buttons
•Socket for Capacitive Touch Pad daughter board (Touch TWRPI)
•Socket for Tower Plug-in (TWRPI, e.g. sensor board)
•Standalone USB host and device function
•Microphone and buzzer
•Potentiometer
•MMA8451Q three-axis accelerometer
•Battery holder for 20mm lithium battery (e.g. 2032, 2025)
•Board power select with 3.3V or 1.8V MCU operation
Figure 1. Front side of TWR-K20D72M module

TWR-K20D72M User’s Manual Page 5 of 17
Figure 2. Back side of TWR-K20D72M module
1.2 Getting started
Follow the Quick Start Guide found printed in the TWR-K20D72M box or the interactive DVD for the list
of recommended steps for getting started. There are also lab walk-through guides available on the
tool support page for the TWR-K20D72M: http://www.freescale.com/TWR-K20D72M.
1.3 Reference Documents
The documents listed below should be referenced for more information on the Kinetis family, Tower
System and the MCU modules. These can be found in the documentation section
of http://www.freescale.com/TWR-K20D72M or http://www.freescale.com/kinetis.
•TWR-K20D72M Quick Start Guide
•TWR-K20D72M Schematics
•K20 Family Product Brief
•K20 Family Reference Manual
•Kinetis Quick Reference User Guide (KQRUG)
2Hardware Description
The TWR-K20D72M is a Tower System module featuring the MK20DX256VLL7 – an ARM® Cortex-M4™
based microcontroller with USB 2.0 full-speed OTG controllers in a 100LQFP package with a maximum
core operating frequency of 72MHz. It is intended for use in the Freescale Tower System but can
operate stand-alone. An on-board debug circuit, OSJTAG, provides a JTAG debug interface and a
power supply input through a single USB mini-AB connector. Figure 3 shows a block diagram for the
TWR-K20D72M.The following sections describe the hardware in more detail.

TWR-K20D72M User’s Manual Page 6 of 17
OSJTAG
JTAG, Power, SCI K20D72M
100 LQFP
(socket-IC
footprint)
USB
Mini-AB
Tower Elevator Expansion Connectors
I
2
S, SPI, I
2
C, USB, ADC, DAC, FTM, UARTs, Flexbus
8 MHz XTAL
SCI
Freescale Silicon External Connectors Interface Circuits Power
MMA8451Q
Infrared Port
IR Output
I
2
C
20-Pin
Header
Comparator
GPIO / Interrupts
ADC
Reset
LED
5V
32.768 KHz XTAL
3.3V
5.0V
Tower Plug-in
(TWRPI)
Sensor Socket
SPI, I
2
C, ADC, GPIO
Tower Plug-in
(TWRPI)
Touch
TSI, GPIO Capacitive
Touch
Pads
LED
LED
LED
Microphone/
amplifier
ADC
JTAG
USB Device/host
Micro
USB
VBAT (RTC)
General purpose
Tower Plug-in
(TWRPI)
3.3V
Regulator
1.8V
Regulator
Battery holder
Buzzer FTM
Figure 3: TWR-K20D72M Block Diagram
2.1 K20D72M Microcontroller
The TWR-K20D72M module features the MK20DX256VLL7.The Kinetis K20 microcontroller family is
part of the Kinetis portfolio of devices built around an ARM® Cortex-M4™ core. Refer to the K20
Family Product Brief and the K20 Family Reference Manual for comprehensive information on the
MK20DX256VLL7 device. MK20DX256VLL7key features:
•32-bit ARM Cortex-M4 core with DSP instructions
•72MHz maximum core operating frequency
•100LQFP, 14mm x 14mm, 0.5mm pitch package
•1.71V – 3.6V operating voltage input range
•256 Kbytes of program flash, 64 Kbytes of static RAM
•External bus interface
•Power management controller with 10 different power modes
•Multi-purpose clock generator with PLL and FLL operation modes
•16-bit SAR ADC, 12-bit DAC
•High-speed analog comparator with 6-bit DAC

TWR-K20D72M User’s Manual Page 7 of 17
•Programmable voltage reference
•USB full-speed/low-speed OTG/Host/Device controller with device charge detect
•SPI, I2C (w/ SMBUS support), UART (w/ ISO7816 and IrDA), CAN, I2S
•GPIO with pin interrupt support, DMA request capability, digital glitch filtering
•Capacitive touch sensing inputs (TSI)
•Debug interfaces: JTAG, cJTAG, SWD
•Trace: TPIO, FPB, DWT, ITM
2.2 Clocking
The Kinetis MCUs start up from an internal digitally controlled oscillator (DCO). Software can enable
one or two external oscillators if desired. The external oscillator for the multipurpose clock generator
(MCG) module can range from 32.768 KHz up to a 32 MHz crystal or ceramic resonator. The external
oscillator for the real time clock (RTC) module accepts a 32.768 kHz crystal.
Two crystals are provided on board for clocking the K20D72M device: 8 MHz crystal as main oscillator
to clock MCG module and 32.768 kHz crystal for clocking RTC module.
2.3 System Power
In standalone operation, the main power source for the TWR-K20D72M is derived from the 5.0V input
from either the USB mini-B connector, J14 or the debugger header, J11, when a shunt is placed on
jumper J10. On board low-dropout regulator provides either 3.3V or 1.8V supply from the 5.0V input
voltage based on jumper settings on J17, refer to sheet 5 of the TWR-K20D72M schematic for details.
When installed into a Tower System, the TWR-K20D72M can be powered from either an on-board
source or from another source in the assembled Tower System. If both the on-board and off-board
sources are available, the TWR-K20D72M will default to the off-board source.
The 3.3V or 1.8V power supplied to the MCU is routed through a jumper, J6. The jumper shunt can be
removed to allow for either 1) alternate MCU supply voltages to be injected or 2) the measurement of
power consumed by the MCU.
2.3.1 Board Power Select
TWR-K20D72M board include on board regulators for both 3.3V and 1.8V output and add jumper J17
to select which one to use as board power and CPU power. This allows MCU operation under 1.8V
power supply.
2.3.2 RTC VBAT
The real time clock (RTC) module on the K20D72M has two modes of operation, system power-up and
system power-down. During system power-down, the RTC is powered from the backup power supply,
VBAT. The TWR-K20D72M provides a battery holder for a coin cell battery that can be used as the

TWR-K20D72M User’s Manual Page 8 of 17
VBAT supply. The holder can accept common 20mm diameter 3V lithium coin cell batteries (e.g. 2032,
2025). Refer to the description J13 in Table 4 “TWR-K20D72M Jumper Table” for more information.
2.4 Debug Interface
There are two debug interface options provided: the on-board OSJTAG circuit and an external Cortex
Debug connector.
2.4.1 OSJTAG
An on-board, MC9S08JM60 based Open Source BDM (OSBDM) circuit provides a debug interface to the
K20D72M. A standard USB A male to Mini-B male cable (provided) can be used for debugging via the
USB connector, J14. The OSJTAG interface also provides a USB to serial bridge. Drivers for the OSJTAG
interface are provided in the P&E Micro Kinetis Tower Toolkit (available on the included DVD).
2.4.2 Cortex Debug Connector
The Cortex Debug connector is a 20-pin (0.05") connector providing access to the SWD, SWV, JTAG,
cJTAG, EzPort signals available on the K20 device. The pinout and K20 pin connections to the debug
connector, J11, is shown in Table 1.
Table 1. Cortex Debug Connector Pinout
Pin Function TWR-K20D72M connection
1 VTref MCU supply (MCU_PWR)
2 TMS/SWDIO PTA3/UART0_RTS_b/FTM0_CH0/JTAG_MS/SWD_DIO
3 GND GND
4 TCK/SWCLK PTA0/UART0_CTS_b/FTM0_CH5/JTAG_CLK/SWD_CLK/EZP_CLK
5 GND GND
6 TDO/SWO PTA2/UART0_TX/FTM0_CH7/JTAG_DO/TRACE_SWO/EZP_DO
7 Key -
8 TDI PTA1/UART0_TX/FTM0_CH6/JTAG_DI/EZP_DI
9 GNDDetect PTA4/FTM0_CH1/MS/NMI_b/EZP_CS_b
10 nReset RESET_b
11 Target Power 5V supply (via J10)
12
-
-
13 Target Power 5V supply (via J10)
14 - -
15 GND GND
16 - -
17 GND GND
18 - -
19 GND GND
20 - -

TWR-K20D72M User’s Manual Page 9 of 17
Note:there are no ETM signals on K20D72M, so the associated signals on Cortex Debugger connector
is left empty.
2.5 USB Interface
TWR-K20D72M board allows using USB as host or device in standalone mode or with connection to
TWR-SER board in a complete tower kit. Jumper J16 can be used to select which USB VBUS signal from
USB connector to connect with the MCU VREGIN input pin. When using in standalone mode, short 5-6
on J16 and connect USB with on board Micro-USB connector J19, when using with TWR-SER board in
complete tower kit, short 6-8 on J16 and connect USB with Mini-AB connector J14 on TWR-SER board.
Refer to description on J16 in Table 4 “TWR-K20D72M Jumper Table” for more information.
2.6 Infrared Port
An infrared transmit and receive interface is implemented as shown in Figure 4 below. The CMT_IRO
pin directly drives an infrared diode. The receiver uses an infrared phototransistor connected to an on-
chip analog comparator through a low-pass filter.
Figure 4: Infrared Port Implementation
2.7 External Bus Interface – FlexBus
The K20 device features a multi-function external bus interface called the FlexBus interface controller,
capable of interfacing to slave-only devices. The FlexBus interface is not used directly on the TWR-
K20D72M.Instead, a subset of the FlexBus is connected to the Primary Connector so that the external
bus can access devices on Tower peripheral modules. Refer to Table 6 “TWR-K20D72M Primary
Connector Pinout“and sheet 8 of the TWR-K20D72M schematics for more details.
2.8 Accelerometer
An MMA8451Q digital accelerometer is connected to the K20 MCU through an I2C interface and a
GPIO/IRQ signal. Refer to Table 5 “I/O Connectors and Pin Usage Table” for connection details.
2.9 Potentiometer, Pushbuttons, LEDs
The TWR-K20D72M features two pushbutton switches connected to GPIO/interrupt signals, one
pushbutton connected to the master reset signal, two capacitive touch pad electrodes, four user-

TWR-K20D72M User’s Manual Page 10 of 17
controllable LEDs, and a potentiometer connected to an ADC input signal. Refer to Table 5 “I/O
Connectors and Pin Usage Table” for information about which port pins is connected to these features.
2.10 General Purpose Tower Plug-in (TWRPI) Socket
The TWR-K20D72M features a socket 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 2.
Table 2. TWRPI Socket Pin Description
Left-side 2x10 Connector Right-side 2x10 Connector
Pin Description
1 5V VCC
2 3.3 V VCC
3 GND
4 3.3V VDDA
5 VSS (Analog GND)
6 VSS (Analog GND)
7 VSS (Analog GND)
8
ADC: Analog 0
9 ADC: Analog 1
10 VSS (Analog GND)
11 VSS (Analog GND)
12 ADC: Analog 2
13 VSS (Analog GND)
14 VSS (Analog GND)
15 GND
16 GND
17 ADC: TWRPI ID 0
18 ADC: TWRPI ID 1
19 GND
20 Reset
Pin Description
1 GND
2 GND
3 I2C: SCL
4 I2C: SDA
5 GND
6 GND
7 GND
8
GND
9 SPI: MISO
10 SPI: MOSI
11 SPI: SS
12 SPI: CLK
13 GND
14 GND
15 GPIO: GPIO0/IRQ
16 GPIO: GPIO1/IRQ
17 GPIO: GPIO2/UART0_RX
18 GPIO: GPIO3/ UART0_TX
19 GPIO: GPIO4/ UART0_CTS
20 GPIO: GPIO5/ UART0_RTS
2.11 Touch Interface
The touch sensing input (TSI) module of the Kinetis MCUs provides capacitive touch sensing detection
with high sensitivity and enhanced robustness. Each TSI pin implements the capacitive measurement
of an electrode.
The TWR-K20D72M provides two methods for evaluating the TSI module. There are two individual
electrodes on-board the TWR-K20D72M that simulates pushbuttons. Additionally, twelve TSI signals

TWR-K20D72M User’s Manual Page 11 of 17
are connected to a Touch Tower Plug-in (TWRPI) socket that can accept Touch TWRPI daughter cards
that may feature keypads, rotary dials, sliders, etc.
The pinout for the Touch TWRPI socket is defined in Table 3. Refer to Table 5 “I/O Connectors and Pin
Usage Table” for the specific K20 pin connections to the Touch TWRPI socket.
Table 3. Touch TWRPI Pin Description
Pin Description
1 5V VCC
2 3.3 V VCC
3 Electrode 0
4 3.3V VDDA
5 Electrode 1
6 VSS (Analog GND)
7 Electrode 2
8 Electrode 3
9 Electrode 4
10 Electrode 5
11 Electrode 6
12 Electrode 7
13 Electrode 8
14 Electrode 9
15 Electrode 10
16 Electrode 11
17 ADC: TWRPI ID 0
18 ADC: TWRPI ID 1
19
GND
20 Reset
2.12 Microphone and buzzer
TWR-K20D72M board includes a microphone U16 which connects with one ADC channel to allow audio
recording, there is a low-pass filter implemented before microphone input goes to ADC channel.
Jumper J4 can be used for connection with the ADC channel. There is also a buzzer connected with one
PWM output channel on FTM module, jumper J21 is used for this connection.

TWR-K20D72M User’s Manual Page 12 of 17
3Jumper Table
There are several jumpers provided for isolation, configuration, and feature selection. Refer to the
following table for details. The default installed jumper settings are shown in bold with asterisks.
Table 4. TWR-K20D72M Jumper Table
Jumper Option Setting Description
J1 Infrared Transmitter Connection *ON* Connect PTD7/CMT_IRO/UART0_TX to IR Transmitter (D1)
OFF Disconnect PTD7/CMT_IRO/UART0_TX to IR Transmitter (D1)
J2 Enable Micro USB Power *ON* Enable USB Power control IC U14
OFF Disable USB Power control IC U14
J3 Infrared Receiver Connection *ON* Connect IRDA output to EBI_AD8/PTC7/CMP0_IN1
OFF Disable IRDA output to EBI_AD8/PTC7/CMP0_IN1
J4 Microphone connection *ON* Connection Microphone to ADC1_DP0
OFF Disable Microphone to ADC1_DP0
J6 MCU Power selection
*ON* Connect on board VBRD for MCU power supply
OFF Isolate MCU from power supply (allows for external supply or
power measurements)
J10 JTAG Power Connection ON Connect on-board 5V supply to JTAG port (supports powering
board from external JTAG probe)
*OFF* Disconnect on-board 5V supply from JTAG port
J13 VBAT Power Selection
*1-2* Connect VBAT to on-board 3.3V supply
2-3 Connect VBAT to the higher voltage between on-board 3.3V
supply or coin-cell supply
J15 OSJTAG Mode Selection ON OSJTAG bootloader mode (OSJTAG firmware reprogramming)
*OFF* Debugger mode
J16 Power 5V and VREG IN Selection
*1-2* 5V Power from OSBDM USB powers LDO regulator
*5-6* VBUS signal on Micro-USB connector J19 connects to
VREGIN to allow standalone USB operation
6-8
VBUS signal from elevator connector connects to VREGIN
to allow USB operation with complete tower kit
J17 Board power selection
1-2 Board power from VOUT_3V3
*3-5* Board power from 3.3V regulator
5-7 Board power from 1.8V regulator
J18 3.3V VOUT Selection ON Connect USB 3.3V regulator output to MCU_PWR
*OFF*
Disconnect USB 3.3V regulator output to MCU_PWR
J20 USB power IC over-current signal
connection
*ON*
Connect over-current signal on USB power IC MIC-2026 to
PTC8
OFF Disconnect over-current signal on USB power IC MIC-
2026 to PTC8
J21 Enable Buzzer *ON* Enable buzzer to EBI_AD11/FTM0_CH3
OFF Disable buzzer to EBI_AD11/FTM0_CH3

TWR-K20D72M User’s Manual Page 13 of 17
J23 Enable IRQ2 to ACCELEROMETER ON Enable IRQ2 to ACCELEROMETER
*OFF* Disable IRQ2 to ACCELEROMETER
J24 Enable IRQ1 to ACCELEROMETER ON Enable IRQ1 to ACCELEROMETER
*OFF* Disable IRQ1 to ACCELEROMETER
J25 Enable SCL to ACCELEROMETER *ON* Enable SCL to ACCELEROMETER
OFF Disable SCL to ACCELEROMETER
J26 Enable SDA to ACCELEROMETER *ON* Enable SDA to ACCELEROMETER
OFF Disable SDA to ACCELEROMETER
J27 Enable POTENTIOMETER *ON* Enable POTENTIOMETER to ADC1_DM0
OFF Disable POTENTIOMETER to ADC1_DM0
4Input/Output Connectors and Pin Usage Table
Table 5 provides details on which K20D72M pins are using to communicate with the TWR-K20D72M
sensors, LEDs, switches, and other I/O interfaces.
Note: Some port pins are used in multiple interfaces on-board and many are potentially connected to
off-board resources via the Primary and Secondary Connectors. Take care to avoid attempted
simultaneous usage of mutually exclusive features.
Table 5. I/O Connectors and Pin Usage Table
Feature Connection Port Pin Pin Function
Infrared Port IR Transmit PTD7 CMT_IRO
IR Receive PTC7 CMP0_IN1
Pushbuttons
SW1 (IRQ0) PTC1 PTC1
SW2 (IRQ1) PTC2 PTC2
SW3 (RESET) RESET_b RESET_b
Touch Pads Touch PTB0 TSI0_CH0
Touch PTB1 TSI0_CH6
LEDs
D2 / Orange LED PTC4 RESET_b
D3 / Yellow LED 3.3V Power on
D4 / YEL/GRN LED PTD1 OSBDM status
D5 / Yellow LED PTD0 OSBDM target power
D7/Green LED PTC7 Green LED
D8/Blue LED PTC8 Blue LED
D9 PTC9 D9 Electrode LED
D10 PTC10 D10 Electrode LED
Potentiometer Potentiometer (R42) - ADC1_DM0
Microphone Microphone - ADC1_DP0
BUZZER BUZZER PTC4 FTM0_CH3

TWR-K20D72M User’s Manual Page 14 of 17
Accelerometer
I2C SDA PTB3 I2C0_SDA
I2C SCL PTB2 I2C0_SCL
IRQ1 PTB0 PTB0
IRQ2 PTB1 PTB1
General Purpose
TWRPI Socket
TWRPI AN0 (J7 Pin 8) PTB0 ADC0_SE8
TWRPI AN1 (J7 Pin 9) PTB1 ADC0_SE9
TWRPI AN2 (J7 Pin 12) ―ADC1_DP0
TWRPI ID0 (J7 Pin 17) ―ADC0_DP0
TWRPI ID1 (J7 Pin 18) ―ADC0_DM0
TWRPI I2C SCL (J8 Pin 3) PTB2 I2C0_SCL
TWRPI I2C SDA (J8 Pin 4) PTB3 I2C0_SDA
TWRPI SPI MISO (J8 Pin 9) PTD3 SPI0_SIN
TWRPI SPI MOSI (J8 Pin
10) PTD2 SPI0_SOUT
TWRPI SPI SS (J8 Pin 11) PTD4 SPI0_PCS1
TWRPI SPI CLK (J8 Pin 12) PTD1 SPI0_SCK
TWRPI GPIO0 (J8 Pin 15) PTC5 PTC5
TWRPI GPIO1 (J8 Pin 16) PTC6 PTC6
TWRPI GPIO2 (J8 Pin 17) PTD6 UART0_RX
TWRPI GPIO3 (J8 Pin 18) PTD7 UART0_TX
TWRPI GPIO4 (J8 Pin 19) PTD5 UART0_CTS
TWRPI GPIO5 (J8 Pin 20) PTD4 UART0_RTS
Touch Pad TWRPI
Socket
Electrode 0 (J5 Pin 3) PTB0 TSI0_CH0
Electrode 1 (J5 Pin 5) PTB1 TSI0_CH6
Electrode 2 (J5 Pin 7) PTB2 TSI0_CH7
Electrode 3 (J5 Pin 8) PTB3 TSI0_CH8
Electrode 4 (J5 Pin 9) PTC0 TSI0_CH13
Electrode 5 (J5 Pin 10) PTC1 TSI0_CH14
Electrode 6 (J5 Pin 11) PTC2 TSI0_CH15
Electrode 7 (J5 Pin 12) PTA4 TSI0_CH5
Electrode 8 (J5 Pin 13) PTB16 TSI0_CH9
Electrode 9 (J5 Pin 14) PTB17 TSI0_CH10
Electrode 10 (J5 Pin 15) PTB18 TSI0_CH11
Electrode 11 (J5 Pin 16) PTB19 TSI0_CH12
TWRPI ID0 (J5 Pin 17) ―ADC0_DP0
TWRPI ID1 (J5 Pin 18) ―ADC0_DM0

TWR-K20D72M User’s Manual Page 15 of 17
5Elevator Connections
The TWR-K20D72M features two expansion card-edge connectors that interface to Elevator boards in a
Tower System: the Primary and Secondary Elevator connectors. The Primary Elevator connector,
comprised of sides A and B, is utilized by the TWR-K20D72M, while the Secondary Elevator connector
only makes connections to ground (GND). Table 6 provides the pinout for the Primary Elevator
Connector.
Table 6. TWR-K20D72M Primary Connector Pinout
Pin
# Side B Pin # Side A
Name Usage Name Usage
B1 5V 5.0V Power A1 5V 5.0V Power
B2 GND Ground A2 GND Ground
B3 3.3V 3.3V Power A3 3.3V 3.3V Power
B4 ELE_PS_SENSE Elevator Power Sense A4 3.3V 3.3V Power
B5 GND Ground A5 GND Ground
B6 GND Ground A6 GND Ground
B7 SDHC_CLK / SPI1_CLK PTE2 A7 SCL0 PTB2
B8 SDHC_D3 / SPI1_CS1_b A8 SDA0 PTB3
B9 SDHC_D3 / SPI1_CS0_b PTE4 A9 GPIO9 / CTS1 PTC9
B10 SDHC_CMD / SPI1_MOSI PTE1 A10 GPIO8 / SDHC_D2 PTB22
B11 SDHC_D0 / SPI1_MISO PTE3 A11 GPIO7 / SD_WP_DET PTB21
B12 ETH_COL A12 ETH_CRS
B13 ETH_RXER A13 ETH_MDC
B14 ETH_TXCLK A14 ETH_MDIO
B15 ETH_TXEN A15 ETH_RXCLK
B16 ETH_TXER A16 ETH_RXDV
B17 ETH_TXD3 A17 ETH_RXD3
B18 ETH_TXD2 A18 ETH_RXD2
B19 ETH_TXD1 A19 ETH_RXD1
B20 ETH_TXD0 A20 ETH_RXD0
B21 GPIO1 / RTS1 PTC7 A21 SSI_MCLK PTC8
B22 GPIO2 / SDHC_D1 PTE0 A22 SSI_BCLK PTB18
B23 GPIO3 PTB20 A23 SSI_FS PTB19
B24 CLKIN0 A24 SSI_RXD PTC11
B25 CLKOUT1 PTE26 A25 SSI_TXD PTC0
B26 GND Ground A26 GND Ground
B27 AN7 PTB0 A27 AN3 ADC0_DP0
B28 AN6 PTB1 A28 AN2 ADC0_DM0
B29 AN5 PTB2 A29 AN1 ADC1_DP0
B30 AN4 PTB3 A30 AN0 ADC1_DM0
B31 GND Ground A31 GND Ground
B32 DAC1 A32 DAC0 DAC0_OUT
B33 TMR3 A33 TMR1 PTA13
B34 TMR2 PTD7 A34 TMR0 PTA12
B35 GPIO4 PTA14 A35 GPIO6 PTA15
B36 3.3V 3.3V Power A36 3.3V 3.3V Power
B37 PWM7 A37 PWM3 PTC4
B38 PWM6 PTD6 A38 PWM2 PTC3
B39 PWM5 PTD5 A39 PWM1 PTC2
B40 PWM4 PTD4 A40 PWM0 PTC1
B41 CANRX0 PTA13 A41 RXD0 PTD6

TWR-K20D72M User’s Manual Page 16 of 17
Pin
# Side B Pin # Side A
Name Usage Name Usage
B42 CANTX0 PTA12 A42 TXD0 PTD7
B43 1WIRE A43 RXD1 PTE1
B44 SPI0_MISO PTD3 A44 TXD1 PTE0
B45 SPI0_MOSI PTD2 A45 VSS VSSA
B46 SPI0_CS0_b PTD0 A46 VDDA VDDA
B47 SPI0_CS1_b PTD4 A47 VREFA1
B48 SPI0_CLK PTD1 A48 VREFA2
B49 GND Ground A49 GND Ground
B50 SCL1 PTB2 A50 GPIO14 PTC12
B51 SDA1 PTB3 A51 GPIO15 PTC13
B52 GPIO5 / SPI0_HOLD/IO3 PTC10 A52 GPIO16 PTC14
B53 USB0_DP_PDOWN A53 GPIO17 PTC15
B54 USB0_DM_PDOWN A54 USB0_DM USB0_DN
B55 IRQ_H PTE25 A55 USB0_DP USB0_DP
B56 IRQ_G PTE24 A56 USB0_ID
B57 IRQ_F PTE6 A57 USB0_VBUS USB0_VBUS
B58 IRQ_E PTE5 A58 TMR7
B59 IRQ_D PTA17 A59 TMR6
B60 IRQ_C PTA16 A60 TMR5
B61 IRQ_B PTC6 A61 TMR4
B62 IRQ_A PTC5 A62 RSTIN_b RESET_b
B63 EBI_ALE / EBI_CS1_b PTD0 A63 RSTOUT_b PTE1
B64 EBI_CS0_b PTD1 A64 CLKOUT0 PTC3
B65 GND Ground A65 GND Ground
B66 EBI_AD15 PTB18 A66 EBI_AD14 PTC0
B67 EBI_AD16 PTB17 A67 EBI_AD13 PTC1
B68 EBI_AD17 PTB16 A68 EBI_AD12 PTC2
B69 EBI_AD18 PTB11 A69 EBI_AD11 PTC4
B70 EBI_AD19 PTB10 A70 EBI_AD10 PTC5
B71 EBI_R/W_b PTC11 A71 EBI_AD9 PTC6
B72 EBI_OE_b PTB19 A72 EBI_AD8 PTC7
B73 EBI_D7 PTC8 A73 EBI_AD7 LATCH_AD7
B74 EBI_D6 PTC9 A74 EBI_AD6 LATCH_ AD6
B75 EBI_D5 PTC10 A75 EBI_AD5 LATCH_ AD5
B76 EBI_D4 PTD2 A76 EBI_AD4 LATCH_ AD4
B77 EBI_D3 PTD3 A77 EBI_AD3 LATCH_ AD3
B78 EBI_D2 PTD4 A78 EBI_AD2 LATCH_ AD2
B79 EBI_D1 PTD5 A79 EBI_AD1 LATCH_ AD1
B80 EBI_D0 PTD6 A80 EBI_AD0 LATCH_ AD0
B81 GND Ground A81 GND Ground
B82 3.3V 3.3V Power A82 3.3V 3.3V Power

TWR-K20D72M User’s Manual Page 17 of 17
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