Re: New Packet Radio Calculator Interface


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Re: New Packet Radio Calculator Interface



Hey Mike,
Cool idea, heres some info I copied off the TI site.

Chris

                             Texas Instruments

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                              TI-83 Link Port

     _________________________________________________________________

        TI83 LINK PORT
        --------------

        This brief look at the TI-83 link port shows how to access
        the port and use it for basic sending and receiving of bytes of
        data.

        The TI-83 link port uses 2 data lines, D0 & D1, for
communicating.
        These data lines are accessed through the B-port of the Z80.
        The symbol BPORT is equated to the correct port value in
        the include file "TI83ASM.INC".

        Note :  THE DATA LINES ARE READ IN AS HIGH (1) WHEN NO
                ACTIVITY IS PRESENT ON THE DATA LINES.

                THE LOWER 2 BITS OF THE B-PORT, BITS 0 AND 1, ARE FOR
                WRITING TO THE DATA LINES.

                BITS 2 AND 3 OF THE B-PORT ARE FOR READING IN THE STATUS
                OF THE DATA LINES.


        Reading the data lines :


                IN      A,(BPORT)       ; READ THE VALUE OF THE B-PORT
                CP      0Ch             ; ANY DATA LINE GO LOW ?
                JR      Z,NO_ACTIVITY   ; IF READ 0Ch THEN NO LINES LOW

                CP      8               ; IS D0 PULLED LOW ?
                JR      Z,D0_LOW        ; YES, BIT 2 = 0 SO D0 IS LOW NOW
               ;
               ; ELSE BIT 3 WAS LOW (ACC=4), SO D1 IS LOW
               ;


        Writing to the data lines :

                There are symbols equated to the correct values
                to "OUT" to the B-PORT for controlling the
                status of the data lines.

                LD      A,D0LD1L
                OUT     (BPORT),A    ; is used for setting D0 low, D1 low

                LD      A,D0LD1H
                OUT     (BPORT),A    ; is used for setting D0 low, D1
high

                LD      A,D0HD1L
                OUT     (BPORT),A    ; is used for setting D0 high, D1
low

                LD      A,D0HD1H
                OUT     (BPORT),A    ; is used for setting D0 high, D1
high


        A few of the TI-83 system routines concerning the link port
        are availble for ASM use. These routines are accessed by making
        a call to the routine _IO_EXEC, with a value stored in the
        byte at ASM_IND_CALL (80C8h).

        _IO_EXEC = 51EFh

        D0LD1L      EQU              0C3h
        D0LD1H      EQU              0C1h
        D0HD1L      EQU              0C2h
        D0HD1H      EQU              0C0h
        BPORT       EQU              0



        ASM_IND_VALUE
        -------------

            19d         REC1STBYTE : This routine goes into idle
                                     or low power mode and waits for
                                     the data lines to change. Then
                                     reads a byte of data using the TI-83
                                     bit protocol. This only reads the
1st
                                     byte of data. The byte is returned
                                     in the accumlator.

            20d         REC1STBYTENC : The same as REC1STBYTE except
                                       that the cursor does not flash.
                                       The byte is returned in the
                                       accumulator.

            22d         RECABYTE     : This routine looks at the data
                                       lines for activity for about
                                       2 seconds and reads in a single
                                       byte of data. If no data is found
                                       an error will be generated.
                                       The byte is returned in the
                                       accumulator.

            11d         SENDABYTE    : This routine sends a byte of
                                       data across the data lines
                                       using the TI-83 bit protocol. If
                                       there is no response within about
2
                                       seconds an error is generated.
                                       The data to be sent needs to be in
                                       the accumulator.

     _________________________________________________________________



On Wed, 14 Jan 1998 18:03:11 -0800 Mike Leister <leister@BAGHWAN.NSC.COM>
writes:
>I am working on a short range radio remote control.  The hardware is =
>coming along, and I've just started the software (thanks to Adam at =
>dimension TI) and I need to know how to control the linkport.  Please
>=
>respond with sample code if you can.
>
>The remote control will operate on the 902MHz to 928MHz no-license
>band. =
> The frequency can be controlled, and the receiver  will have a four
>bit =
>address, to allow more than one transmitter and receiver to operate at
>=
>the same time.
>
>Now that my assembly programming is off the ground, the project can
>move =
>forward again.
>
>Any help on controlling the linkport would be greatly appreciated.
>
>Mike
>
>
>
>-----Original Message-----
>From:   Grant Stockly [SMTP:gussie@ALASKA.NET]
>Sent:   Tuesday, January 13, 1998 8:07 PM
>To:     CALC-TI@LISTS.PPP.TI.COM
>Subject:        New Packet Radio Calculator Interface
>
>I've devolped a protocall.  Bad thing:  Sending 1k will take about 10
>to =
>40
>seconds depending on the day.  I will have a 500 watt transmitter with
>a
>200 foot antenna at my house which will serve the calcs.  Right now
>its =
>12,
>but I've been wanting to expand it for a long time.  Don't worry.  I =
>live
>in alaska, but I can easily talk to jappan, South dakota, Mariland.  =
>Since
>short waves bounce off of the atmosphere, you guys might need to amp
>up
>your signal.  I can send to you, but you may not be able to send (very
>well) to me on a cloudy day.  (it might take a minute to do 1k)
>
>If you lived on the west coast, we could get 9600bps talkin to each =
>other... :)
>
>I will release new information when I make it.  It won't be exactly
>500
>watt for very some time.  The more hubs I sell, the sooner.  takes =
>arround
>$8,000 for everything.  fcc to come and look at it (they don't want
>you
>pumpin' 500 watts into your neighbors TV)/ and making it 200 feet long
>=
>with
>low gauge wire isn't cheep either!  50 watt (now) will easily do all
>of =
>the
>united states, but you guys in france will (maybe) have to wait untill
>summer.
>
>I only have 25MB of ram in my computer (the one I'm giving up for
>radio) =
>so
>only 2,000 calcs can send information at a time.  :)
>
>Grant
>
>
>---
>"Earth Today.  We'll strip mine other planets later."
>


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