SE-8008 Sensor extender

Keyword:

       INHAOS , Arduino , Smart Car , UGV , MassDuino , SE-8008

l  Introduce

The SE-8008 is a sensor expansion board based on MassDuino , the main chip is MD-8088. MD-8088 integrates a wealth of digital peripherals and analog peripherals, it offers great flexibility and play space for the users of the product design. SE -8008 is using SPI to communicate with main processor, it can save a lot of ports, so that we can use the SE-8008 to extend more different sensors from the main system. If you have a need, in this way can also extend other modules from the control board, such as the LE-1600 , RC-1406(Mortor Driver), ADC acquisition module and so on. MD-8088 chip is editable in the Arduino environment, so we can use a USB to serial cable for SE-8008 for upgrade firmware. The module is high performance low power, low cost , and it support secondary development.

About MassDuino , please refer to: http://www.inhaos.com/uploadfile/otherpic/UM-MASSDUINO-V01-EN.pdf

l  Features

Ø  Can be program in the Arduino environment, very easy to use

Ø  Support secondary development

Ø  8K bytes of in-system programmable FLASH, innovative data encryption technology  

Ø  504 bytes of data FLASH, support byte read (simulate E2PROM)

Ø  1K SRAM bytes on-chip

Ø  Programmable synchronous / asynchronous USART

Ø  Can work in master / slave mode SPI Serial Interface

Ø  I2C -compatible two-wire serial communication interface protocols , supporting master and slave device mode

Ø  32 8it general purpose working registers

Ø  Support the expansion of the chip in-circuit debugging functions

Ø  By SWD interface programming for FLASH, EEPROM, system configuration area , the ISP function

Ø  Up to 30 programmable I / O

Ø  High-performance, low -power and low-cost 

l  SPI communication ports

  When we use the SE-8008, we can use the DuPong cable to connect it to the master chip SPI communication port.

l  Pin Description

l  SPI Protocol

  

    The SE-8008 was working in SPI Slave mode , after power on , the chip will wait for command

    form SPI Master ,then implement it if the it received valid command.

    

    The communication protocol as below:

   In the master side , the SPI initial code as below:

 SE-8008 supported command as below:

l  IR Sensor Connection

Below figure show the connection between IR sensor and SE-8008, they are connected via 3 wires: TX / RX and GND.

SENSOR_IR_OFF: the TX will set to "0", the IR will turned off , then read RX by 10bit ADC , this is the background IR signal.

SENSOR_IR_ON: the TX will set to "1", the IR will turned ON, then read RX by 10bit ADC , the signal level depend on the distance of obstacles.

SENSOR_IR_DIFF: the difference between SENSOR_IR_OFF and SENSOR_IR_ON. most IR detector use comparator to shaping the signal with a fixed reference level, when we use IR to detect distance of obstacles , the result is very depends on the environment , for the example , some time the unit is working very good in room , but when you turned light or move to sunlit environment, it will occurred unexpected error , because the light or sunshine have very high IR signal , this will change the background level and make the IR detector working failed. In this case , you can read SENSOR_IR_DIFF , this value will significantly reduce the environment changes impact the detection result.

l  Photo interrupter Connection

The SE-8008 include 8-CH of IR detection and 2-CH of Photo interrupter, the IR detection used to detect distance of obstacles and photo interrupter used to detect wheel rotation speed, Below figure show the photo interrupter connection and how it work. 

Difference with the IR detection circuit, the IR is always powered , and the OPT signal will shaping by a comparator, thinking difference application have difference signal level , so adjust the 10K VR to adjust reference level of the comparator.

l  Arduino Source Code

Two code will coming with this board:

1, SE-8008.rar

    This is arduino source code for SE-8008 , to development the SE-8008 , user need to install

    MassDuino driver, and write code in arduino , and upload sketch via USB2SERIAL light cable,

    the relational link as below:

    MassDuino support package:  http://www.inhaos.com/downcount.php?download_id=139

    USB2SERIAL Light cable: http://www.inhaos.com/uploadfile/otherpic/DOC-BUONO-USB2SERIAL-V01-EN.pdf

2, SE-8008_UNO_MASTER.rar

    This is arduino source code for UNO , the UNO will working with SE-8008, this code demo

    how to use SE-8008 in Arduino.

All code can be download from www.inhaos.com

l  Application:

n  Extend IO and save code for UNO to drive many sensors

n  Arduino car / robotics

n  Sensor drive

n  Toy