Re: TI-H: Radio link.
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Re: TI-H: Radio link.
This is the situation. When the link listening to no signal you always get a
logical '0' out. So your thing doesn't work so nice. But it gave me a idea I
probably had two years ago ( It is good to reinvent the wheel : ) ). First
when you go in and listening you assume that the other link has two logical
'1'. Then when you get a low pin from the TI example '0' from pin 0 you send
the sequence '10'. When the pin goes high you send the same sequence again.
For pin 1 this sequence become 11. You send a sequence on change. I don't
think this can be more efficient encoding if you don't take care of the
whole byte. If you transmitting with TI:s own protocol it is more efficient
to swap a
byte and then transmit it with in a more efficient way ex. RS-232. Why
RS-232 then? Because it is hardware supported in the AVR risc
microcontroller. You can't beat that with software in the link to link way.
Thank you for your
suggestion.
/PEA
At 02:26 1999-10-29 -0800, you wrote:
>
>Your bit status isn't clear. Why not just designate bit 0 for pin 0 and
>bit 1 for pin 1? Then just transmit that as fast as you can in packets
>with echo.
>
>Thats the best way to make sure all data gets where it needs to go without
>errors.
>
>Grant
>
>>First I will say that the price was wrong. It should be $10 not $100.
>>I'm sorry for that.
>>
>>I will have a small onechip computer for doing the transfer.
>>The pin state I will send when any pin is low. Maybe this
>>will take a lot of bits send in transmitting. Ex.
>>000 pin 0 is low. 001 pin 1 is low. 010 pin 0 goes high and 011 pin
>>1 goes high. It sending on a change in state of pins. When it's no
>>change the link is in listening mode.
>>This is not so effective as encodeing a protocol and send with RS-232.
>>And if you send with RS-232 or some other homemade protocol you can do more
>>advance faliure secure things.
>>And I have thought of compressing the data also. If you for example send
>>Z80 programs this is a really nice code to pack. But the first thing is
>>to make the state of pin protocol work. It is really good if you people come
>>with some ideas and so on.
>>
>>The radio link is on a swedish page. But I put the .pdf file on
>>www.big.du.se/~pea
>>
>>It is a little tricky to make but the layout is in the pdf-file and
>>that is a relief.
>>
>>/PEA
>>
>>
>>
>>
>>At 13:02 1999-10-28 -0500, you wrote:
>>>
>>>From: Grant Stockly <gussie@stockly.com>
>>>>>First I going to have a direct connection. The link looks just like a
>>>cable
>>>>>to the TI.
>>>>>Then you should be able to switch a switch were the link can recognize
>>>>>different protocols from TI ex. I2C. Between the links there will be
>>>>>RS-232 maybe with some multi-user support. You have transfer rate of 9.6
>>>Kbps.
>>>>
>>>>Why don't you save yourself and others time by just transmitting line level
>>>>state over the radio? Any protocol can be used (even RS232) and the thing
>>>>would work great.
>>>
>>>Sounds like that is what the first mode was. That would be the prefered way
>>>to do a radio link, since it then supports any protocol the software is
>>>using.
>>>
>>>What I was really asking about was details on the protocol. IE, how are you
>>>going to handle transmitting the state of the wires?
>>>
>>>I'm curious who produces the transceiver you are using, is there a web page
>>>for it somewhere?
>>>
>>>DK
>>>
>>>
>>>
>>>
>>>
>>>
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