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Comment Re: Got my start with Terrapin Logo on an Apple ][ (Score 2) 68

Did you try the .OPTION commands that replaced the pokes?

The C64 port took a long time because of the reduced number of page zero registers available. The biggest problem was that location 0 and 1 were used for the parallel bus port, and there were lots of places where we assumed the CAR of NIL was NIL but instead it was random dat. I had a kernel ROM listing to help with the register usage, and later a 6510 Andy Finkel had fabbed for me to use with a logic analyzer to disassemble and set breakpoints on memory access for the 0 problem.

I never got the interrupts right for doing setspeed with the sprites... sorry about that.

Submission + - HP-15C, HP-16C & HP-41CX Reborn!!! The world's smallest programmable RPN cal 2

mikesters writes: SwissMicros produces clones of the famous HP calculators from the 1980's: the HP-11C, HP-12C, HP-15C, HP-16C and also of the HP-41CX.

More than ten years ago an online petition was started to Bring Back the HP-15C. Tens of thousands signed that petition, but HP still won't bring it back into general production.

In 2011 SwissMicros started production of a credit-card sized clone of the HP-15C and some of the other models.

Now in 2015 SwissMicros has released a full-sized clone of the HP-15C and HP-16C as well as of the HP-41CX, fully functional, with real buttons just like the HP calculators and even more features, with high quality materials and finishing.

The calcualtors emulate the original HP ROMs, but alternative ROMs with extended memory capabilities can be user-installed using an USB cable.

Could be the perfect Christmas gift for the nerd who has everything! Go to

Comment Re:Aha (Score 1) 212

The hangers are the adult stage, and if you open your closet very quickly sometimes you can catch them mating.

I told this joke in Japan once and got a polite explanation that (1) socks don't go missing because Japanese people usually hang up their laundry to dry (2) they don't keep other people's pens because they are other people's property and besides they have their own pens (3) hangers don't accumulate because they return them to the cleaners.

Comment Other QRSS modulation projects (Score 3, Informative) 82

This modulation scheme is called QRSS and can also be used to send very low power (milliwatt and microwatt) signals around the world ionospherically, and on bands such as VLF (very low frequency). Here the open source from a couple of projects by Hans Summers from a book I edited for the ARRL on the Arduino: and plenty of links about QRSS from there.

Comment Re:Smart move (Score 2) 457

Voltage? Not 5V? I took a quick look through the USB Power Delivery docs and didn't see that.
Wikipedia doesn't mention it either, though it does discuss the raising of the pre-negotiation current limit from 0.5A to 1.5A, and the max negotiated limit at 5A, which would be 25W.

Do you have any links on the higher voltages?

You probably already understand, but many do not, that you cannot push or provide current at 5V that the device doesn't want. If your device will draw only 500mA due to its internal design, attaching it to a 2A or 5A port won't do anything.

Comment Re:Symbolics, Lisp Machines, RMS, GNU EMACS (Score 1) 201

Carl Hewitt's "Actor" model, which is the basis for Erlang, was first implemented on multi-server systems on Symbolics Lisp Machines at the MIT-AI lab. The CADR machines could not be produced fast enough to dedicate enough to the project but when commercial ones were available Carl got a grant and bought 6 of them and they called it the Apiary. They didn't use it all the time so i thought of it mostly as a source of free machines, and we are now only just getting to the point where the multi-CPU network based shared nothing architecture begins to be a mainstream approach.

Comment Careful setting dates (Score 1) 169

In late 1999, we tested a product by rolling the date forward to 2000-01-01 and it worked fine. Then we rolled the date back to the normal date, and files that got touched during the test period caused trouble, because their modification date was "IN THE FUTURE!?!?!?" as one piece of code put it. The most broken was the timestamp data for a time-based UID generator, which flat out refused to run, saying that it was in danger of generating collisions.

Comment Re:The Internet Archive already has a good design (Score 1) 69


Yes, that's in the original submission, as you see above. For the record, Brewster Kahle (who founded, Jeff and Danny (who did this project), and I are all MIT alums, and the "Internet Archive scanning robot" is from a company called Kirtas, which also has ties to Xerox.

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