Re: TI-H: External Refrence Clock
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Re: TI-H: External Refrence Clock
Some ISPs don't let you dial in at 2400...
>Well, you should be working on a TI-modem.. the wonderful modem could dial
>up to an ISP with lovely, elegant software that is quite superb in many ways.
>It could dial up, shake hands with the ISP, chat for a bit, send user/pass,
>acknowledge login, and boom.. hooked up. WWW, telnet, and email programs
>for the TI calcs would be booming by the tons... it is just like a palm
>pilot, minus a lot of things like the stylus, yet better than WinCE,
>because... There is NO start button!!!
>
>At 04:45 PM 12/20/98 -0900, you wrote:
>>
>>I don't know if anyone is interested, but I've found that an external
>>refrence source can be used to build a perfect working uart or TC.
>>
>>All you have is an external 555 that generates a pulse, either depending if
>>you'r using a clock or using serial.
>>
>>2400bps over a modem is possible, with no graphlink.
>>
>>All the pulse is used for is to calibrate a delay loop. Kinda like intel's
>>super hot cookers. When the OS starts up it calibrates a delay loop that
>>it uses as a refrence. As the processor gets hotter, there is less of a
>>delay in bus timing and junk like that.
>>
>>I think mine is 791.7MIPS (300MHz) after running with the case off for a
>>week.
>>
>>And a 333MHz gets about 860.3MIPS (no case or processor fans). IBM hasn't
>>released the specs for the 720MHz one. :(
>>
>>A 350MHz cyrix (RISC based pent) gets a 810.2MIPS rating with the case on
>>and dual processor fans. :)
>>
>>I have no processor fans.
>>
>>Keeping calcs cool would make them run faster, but since everything in the
>>calc is based on the charge/discharge of a cap, calcs are more extreme.
>>
>>We could also hook up an external UART to the calc and easily to 300, 600
>>and if the software is compact 1200bps.
>>
>>What would be possible is using jumper wires to an internal processor...
>>The Z80 can be disabled (just paused) and then a second processor could
>>take over the bus. This would be good for doing things like the ultimate
>>mem expander or for realy huge math things. A TI-82 could do 3d surface
>>maping faster than the TI-92.
>>
>>little tiny 200MHz hitachi RISC processors are about the size of inverters.
>>I'd like a second processor like that!
>>
>>I think its totally GAY that a 486/586 will crash with no fan or case.
>>Man, they get hot.
>>
>>Hmmm... Maybe since the calc doesn't get hot, its not working hard enough.
>>:) I know when I push my 300MHz computer to 420MHz it needs a fan, so lets
>>try making an external variable osc circut and see how high we can crank it
>>up! :)
>>
>>
>-Dan
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