KeKePad is a new generation of platform for wearable and e-textile projects. It’s 100% compatible with Arduino LilyPad USB, you can programme it with Arduino IDE. It uses an ATmega32u4 chip and has built-in USB support function, so you can connect KeKePad to your computer directly by a Micro-USB cable and program it.
Traditional wearable and e-textile platforms use conductive thread for wiring. The conductive thread is expensive and has many drawbacks in electronics, it’s bare without any insulation, its resistance is very high.
KeKePad platform introduces a new way of wiring and connection. We get rid of conductive thread and use super tiny Ke connectors and ultra thin Ke cables for the whole platform. The cable wire diameter is only 0.32mm, and is flexible like thread, it’s ultra-thin, strong and smooth with Teflon insulation.
KeKePad controller board is small, it has a round shape (50mm in diameter), there are 12 tiny 3-Pin Ke Connectors and 11 sewtab pins, provides full interfaces for the applications. (Please refer to the Pin Mapping for details).
- Fully Arduino Compatible;
- USB Compatible: Easy to Program;
- Two systems of interfaces: Ke Connectors and sewtab pins;
- Compatible with the existing wearable modules using conductive thread;
- Tiny and high quality;
- Microcontroller: ATmega32u4
- Operating Voltage: 3.3V
- Input Voltage: 3.7V to 9V (Max. 6v is recommended)
- Flash Memory: 32 KB (ATmega32u4) of which 4 KB used by bootloader
- SRAM: 2.5 KB
- EEPROM: 1 KB
- Clock Speed: 8 MHz
- Power Input: BAT_IN Port (3-Pin Ke Connector)
- Power Output: Pin1(+) and Pin3(-) of Port 1, 2,4,5,6,10 is 3.3v and GND; The Port BAT_OUT has an unregulated output (VBAT) directly from the battery
- Dimensions: 50mm in diameter (PCB thickness: 1.2mm, Max. height with components: 4.4mm)
- Weight: 9g
The power supply for KeKePad is either from MicroUSB or from the BAT_IN port.
Just connect the Coin Cell Battery Holder or a Li-polymer battery (you may need to use the Switch/Adapter) to KeKePad BAT_IN Port with Ke Cables to power it.
The regulator on KeKePad is MCI5219, it can work at Max. 12V input voltage, but we recommend the Max. voltage at 6V in normal usage.
The KeKePad has a slide switch on board, it can switch the board power supply on or off.
For safe usage, we do not include the charging circuit on KeKePad, but provide a battery charger module for Li-Po batteries.
There are 3 indicator LEDs on KeKePad: RX, TX LEDs (will flash when transmitting data )and User LED.
As shown below in the Table, the modules are connected to the KeKePad controller board by Ke Cables.
To simplify the connection, only 3-pin Ke connectors are introduced in the platform. Some modules only have 1 pin for signals, so one connector is enough (VCC S GND); Some modules use USART, I2C or SPI communication, so there are two 3-pin connectors on the modules, one is for power and another one is for signals, the ports with VCC and GND (P1, P2, P4, P5, P6, P10 and BAT_OUT ) can all be used as the power supply ports;
There are 12 functional pins (D7,D10,D6,D9,D12,D5,D11; A5,A8,A3,A4,A2) together with USART, I2C and SPI interface for all kinds of applications. Each of the pins can be used as input or output and have the same functions as on LilyPad Arduino USB.
Some of the Pins have specialized functions:
PWM: D6, D10, D5, D9, D11, these pins provide an 8-bit PWM output, please refer to Arduino analogWrite().
UART: RX(D0), TX(D1). These pins are used for serial communication.
I2C(TWI): SCL(D3), SDA(D2), these are I2C communication pins, please refer to Arduino Wire library.
Please see the Pin Mapping below:
This Table shows the compatible ports on KeKePad for the Modules.
|Ke Light Sensor||Analog light sensor TEMT6000||P2; P4; P5(A10); P6(A9);|
|Ke UV Sensor||Analog UV sensor ML8511||P2; P4; P5(A10); P6(A9);|
|Ke Color Sensor||I2C color sensor TCS34725||P8 + Port with VCC 3.3v (P1,2,4,5,6,10);|
|Ke Barometer||I2C barometer BMP180||P8 + Port with VCC 3.3v (P1,2,4,5,6,10);|
|Ke Temp. and Humidity Sensor||I2C temp. and humidity sensor Si7021||P8 + Port with VCC 3.3v (P1,2,4,5,6,10);|
|Ke Accelerometer||Analog accelerometer ADXL335||P3 + Port with VCC 3.3v (P1,2,4,5,6,10)|
|Ke Vibration Sensor||Digital vibration sensor||P1|
|Ke Vibration Motor||PWM||PWM(P5, P6, P10, BAT_OUT)|
|Ke Buzzer||PWM||PWM(P5, P6, P10, BAT_OUT)|
|Ke Sound Detector LMV324||Analog sound sensor with 3 input||P3 + Port with VCC 3.3v (P1,2,4,5,6,10)|
|Ke Sound Detector||Analog sound sensor with 1 input||P2; P4; P5(A10); P6(A9);|
|Ke MP3 V1.0||USART||P7|
|Ke Pixel Mini||Digital GRB LED with Integrated IC||P1, P5, P6, P10 and BAT_OUT|
|Ke Pixel Ring||Digital GRB LED with Integrated IC||P1, P5, P6, P10 and BAT_OUT|
|Ke TH Pixel Mini||Digital RGB LED with Integrated IC||P1, P5, P6, P10 and BAT_OUT|
|Ke Smart LED||Digital RGB LED with SMD IC||P1, P5, P6, P10 and BAT_OUT|
|Ke Pixel Stick||Digital GRB LED with Integrated IC||P1, P5, P6, P10 and BAT_OUT|
|Ke Button||Switch button||P1,2,3,4,5,6,10 and BAT_OUT|
|OLED Display||SPI 128*64 OLED screen||P9 + Port with VCC 3.3v (P1,2,4,5,6,10)|
|Ke Li-Po Charger||Power Supply||BAT_IN|
|Ke Coin Cell Battery Holder||Power Supply||BAT_IN|
Ke Connector and Ke Cable is developed by KeKe Smart. Ke Cable is special, because no such thin cables was produced before, with several months’ hardworking, we produced it successfully, the cable wire diameter is only 0.32mm (OD), so it’s the thinnest cable in the world (with crimp terminal), it’s so thin and flexible, we must use Laser Technology in production! The cable has many advantages in wearables and e-textiles.
The Compare of Ke Cable and a Normal JST Cable
Ke Connector is so tiny, it’s only 1/5 the size of a normal 3-pin JST connector; The connector has a hook, when the cable housing is inserted into the wafer, it will be hooked and can not be pulled out unless you press down the hook end.
Tips: Sometimes, the connection is tight, don’t pull the cable to release it! You may break the cable! The right way is pressing down the housing hook-end and push the head of it with your nail.
KeKePad is already pre-burned with a Arduino LilyPad USB bootloader, so you can just upload new sketches into it, no need to use an external hardware programmer.
Just plug into a MicroUSB cable and connect KeKePad with your computer, following the instructions, you can upload sketches to KeKePad and start to use it, for details, please read our Getting Started pages for detail.
Many makers like Li-Po batteries because it’s rechargeable, high-capacity, light and safe. So we designed this small and compact Li-po battery charger….
Like Ke Pixel Mini, Ke Pixel Ring use the same SMD 5050 pixel LED. Ke Pixel Ring is chainable design, it has 18 LEDs in a ring, with two Ke Connectors on the back. Just connect Ke Pixel Ring’s data in port to KeKePad, connect the data out port to the next pixel ring’s data in port, and you can chain several pixel rings together…
Who don’t like music? If add some vivid music or sounds to the item you make, the effect will be totally different immediately. Ke MP3 V1.0 is an integrated designed MP3 module that can add nice music effects to your projects….
Ke Barometer is a high precision barometric pressure sensor module with an I2C interface. The sensor chip BMP180 is from Bosch, which is a new generation of high precision digital pressure sensors for consumer applications such as mobile phones, PDAs, GPS navigation devices and outdoor equipment….
Ke Color Sensor TCS34725 is a plug-and-play designed module for wearable projects. This module includes a TAOS TCS34725 color sensor chip that provides a digital return of red, green, blue (RGB), and clear light sensing values….
KeKePad is a new generation of platform for making wearable and fabric projects. KeKePad is open source, it’s developed based on LilyPad Arduino USB, but adopts a new way of wiring and connection. It uses an ATmega32u4 chip and has built-in USB support function. You can connect KeKePad to your computer directly by a Micro-USB cable to program it…
Ke Pixel Stick has 6 5050 WS2812B pixel LED surface mounted on a small PCB stick. It has 2 connectors on the back, it’s chainable design, one connector is for data in and another one is for data out…