I'm designing a new kit around the PIC18F67J60 (Ethernet) Opinions wanted

Discussion in 'Embedded Systems and Microcontrollers' started by blueroomelectronics, Nov 17, 2009.

  1. blueroomelectronics

    Thread Starter AAC Fanatic!

    Jul 22, 2007
    I'm putting a new kit together called Ladybug. (yes my kits are named after critters) :)

    On the drawing board is a kit designed for Home automation, HVAC / furnace / AC controller with Ethernet plus it's expandable.

    Before it gets set in stone (PCB layout) I'd like your opinions on the feature set.

    Standard peripherals (100% sure)
    One Ethernet jack with magnetics
    Four Panasonic JS1-5V Relays
    Two opto isolated inputs HCPL-2630
    SPI EEPROM / Flash upto 8Mb
    At least one 8 pin I/O port EasyPIC compatable

    Likely to be there (80%)
    DE9-Male DCE RS232 with HW/SW UART (jumper selectable)
    RS485 SW UART

    On the fence (50% either way)
    XBee / XBee Pro socket with HW/SW UART (jumper selectable)

    Do we need them?
    433MHz RF receiver (handy for digital thermometers)?
    NO/C/NC or NO/C relay outputs?
    32,768Hz watch crystal?

    SD card socket.
    iButton connector (just use an I/O port if you need it)
    Temperature sensors (also can be added via DIY I/O expansion)

    As always your opinions on this would be appreciated.
  2. thatoneguy

    AAC Fanatic!

    Feb 19, 2009
    If it is for controlling a home temperature remotely, why do away with the temperature sensors?

    Along the same lines with environment control, humidity is a nice measurement in winter time.

    Add some sort of X10 interface, that will open a world of other (already existing) "add-ons".
  3. blueroomelectronics

    Thread Starter AAC Fanatic!

    Jul 22, 2007
    Thanks for the feedback.

    The reasons I'm holding off on an onboard temperature sensor are:

    The Ladybug will probably be located in the deep dark recesses of your home IE: near the furnace, in the basement.
    The Oregon Scientific THGR268 Temperature / Humidity sensor and transmitter (433Mhz)

    (I suppose I could add a 1-wire (DS18B20) header)

    A little history on me, several years ago I was working on a thermostat kit you could program yourself. Named it Cricket and have designed and built several prototypes.
    Ultimately the Cricket kit may never exist because of inexpensive devices like the $30 THGR268
    A THGR268
    The Ladybug will have expansion connectors and possibly an 2x7 LCD header (no backlight)

    X10 support would be possible via the RS232 connector using a CM11A (Personally I find the ancient X10 stuff very unreliable, your mileage may differ)

    A 16F917 Cricket Thermostat prototype