TWR-KL28Z Hardware Description
TWR-
KL28Z User’s Guide, Rev. 0, 06/2016
6
NXP Semiconductors
MCU, cut the jumper between pin1 and pin2 of J32/J33 on bottom layer. This will disconnect the
SWD_CLK pin to the KL28Z so that it will interfere with the communications to an off-board MCU
connected to J30.
Figure 5
shows SWD connector signals description for KL28Z.
Figure 5. SWD debug connector to KL28Z
4.2.2. Virtual serial port
A serial port connection is available between the CMSIS-DAP MCU and pins PTA1 and PTA2 of the
KL28Z. Several of the default CMSIS-DAP applications are provided by NXP, including the MSD
Flash Programmer and the CMSIS-DAP USB HID interface, providing a USB communications device
class (CDC) interface that bridges serial communications between the USB host and this serial interface.
4.3. Microcontroller
The TWR-KL28Z is a MCU module featuring the MKL28Z512VLL7, a Kinetis microcontroller with
USB 2.0 full-speed OTG controller in a 100 LQFP package. An on-board debug circuit, CMSIS-DAP,
provides a SWD interface and a power supply input through a mini-USB connector, as well as serial to
USB and CDC class compliant UART interface.
Table 3.
Features of MKL28Z512VLL7
Feature
Description
Ultra-low-power
- 10 low-power modes with power and clock gating for optimal peripheral activity and
recovery times. Stop currents of <190 nA (VLLS0), run currents of <280 uA/MHz, 4 s wake-
up from Stop mode
- Full memory and analog operation down to 1.71 V for extended battery life
- Low-leakage wake-up unit with up to eight internal modules and eight 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, SRAM, ROM
- 512 KB flash featuring fast access times, high reliability, and four levels of security
protection. No user or system intervention to complete programming and erase functions
and full operation down to 1.71 V
- 128 KB of SRAM
- 32 KB of ROM with Kinetis bootloader included (UART, SPI, I
2
C, USB-HID)
