Re: TI-H: Linking Speed - was Re: Modem
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Re: TI-H: Linking Speed - was Re: Modem
On Sat, 31 May 1997 21:24:52 +0000, you wrote:
>Sami Khawam wrote:
>>
>> I'm the one who dsigned the PICLink (see my page). THe
>> current problem is the the computer is sending data to
>> fast( at 9600 bps); When the PIC is still sending a byte
>> to the calc, the computer starts sending the next byte.
>>
>> I wanted to know the fastest speed the calc can handel,
>> I used my computer to mesure it ( a parallel link, the
>> calc was runnig TALK), and I found that it was something
>> like 2500 bps! I don't know where is the problem, maybe
>> at the program that is runnig on the calc, TALK, (with
>> ZTerm it was even slower), or maybe at my calc?
>
>I'd guess it's the program, because the speed of the link port largely
>depends on how fast the software can handle it. ZShell routines like
>CALL_ and JUMP_ spend much processor time, so they should be avoided in
>time-critical routines like those that handle the link port. At some
>stage, the link port hardware refuses to work on very high speeds, but
>(according to Mel Tsai) you should still get much faster transfer speeds
>than your 2500 bps. I think the maximum was over 30kbps...
Right... in my expander driver software I must place NOP instructions
between IN 7, * and OUT 7,* instructions otherwise it'll overrun the
link port. But, the TI protocol is very inefficient so you'll be very
lucky to get 9600 bps. But with complete software control it's around
35kbps.
-mel
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