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View Full Version : Shields Up!



dhouston
- 30th May 2011, 01:10
I have a tentative arrangement with someone to produce the ConnectOne ethernet shield as well as the Tibbo EM500/GA1000 shield (in the event Tibbo releases the long-promised firmware which I have been patiently awaiting for over a year:rolleyes:).

They also can modify a bootloader to support the use of the PIC16F88 and PIC16F886/887 comparators to invert TX & RX eliminating the need for RS232 line driver and caps, further reducing the cost of the XINO and XINO Basic use as a simple development system. (I don't know whether this cheat will work at 3.3V.)

mackrackit
- 30th May 2011, 13:54
Would the PIC16F88 and/or PIC16F886/887 replace the PIC18F25K20? Or would they be part of the shield?

Might be interesting, for the ConectOne, to have a PIC on the shield with the AT commands "library". Kind of like a LCD serial back-pack.

Just a quick thought... How to code it? Requires more thought... :confused:

dhouston
- 30th May 2011, 17:29
My thinking was to use the PIC on the main board for those who would rather not use PICAXE. I think the latest PICAXE chips are the 18M2 and 28X2 which are custom made PICs which I've yet to see datasheets on - I just started this yesterday. Since I know a smattering of PBP, I'd rather go that way.

I was drawn to this by the ultra-low cost educational potential of the XINO basic board. If they can modify the bootloader (and add current limiters on TX/RX) this could be powered from a USB port, a crank-style generator or a solar panel. A PIC on the shield would add cost - I'd prefer a ??KB I2C FRAM as an option to store AT codes. FRAM gets costly above 8KB or so but it's non-volatile. It would be more work to code but I assume you are hereby volunteering...:D

You could have a bare-bones development system for $6.84 (Xino kit) (http://www.hotsolder.co.uk/xino-basic-pic-404-p.asp) + $2 (PIC16F88) or for those with deeper pockets $2.25 for the PIC18F25K20. Of course, they also will work with Amicus18 main boards although w/o the small customization tweaks I think we can do on the Xino board.

I've asked about doing an XRF (http://www.hotsolder.co.uk/xrf-radio-data-module-406-p.asp)shield which I think would have enormous potential. I've finished these (except the details awaiting the long-promised Tibbo EM500/GA1000 firmware) and need something to do this afternoon.;)

dhouston
- 30th May 2011, 19:31
FRAM gets costly above 8KB or so but it's non-volatile.Had my brain been in gear :o that would have read that FRAM can be treated like RAM with billions of erase/write cycles which might be an advantage - or not. A 64KB SPI EEPROM is cheap. Even bigger I2C EEPROMs are even cheaper. I'll leave it to the volunteer programmer to advise on this.