Interesting Blog Post (Sci Am, Sept 77)

[Les Bell]

I often check out the Modern Mechanix blog (http://blog.modernmechanix.com/) for its cool reprints of scientific/technical (and social) articles from the last century. A recent entry (http://blog.modernmechanix.com/2010/03/30/ti-micro-electronics/) concerned TI Microelectronics - basically an advertorial or advertising insert in the September 1977 issue of Scientific American. The content describes TI's 9900 series 16-bit microprocessors, and although the insert cover shows various related products, there's also a TI-59 on there - but I didn't think it was based on a 9900 processor; was it?

Anyway, there's several other articles from that particular issue on the same site: http://blog.modernmechanix.com/issue/?magname=ScientificAmerican&magdate=9-1977. The articles mostly related to various early hobby computers, including one on the HP-01. Enjoy!

Best,

--- Les

[http://www.lesbell.com.au]

[Eric Smith]

You are correct that the TMS9900 16-bit microprocessor was not used in the TI-59 calculator, nor in any other TI calculator. The TI-58, TI-58C, TI-59, and SR-60A all used the TMC0501E four-bit processor, specifically design for use in calculators. It is unclear as to what if any, functional differences this had from the TMC0501 processor used in the earlier SR-50, SR-51, SR-52, SR-56, and SR-60 calculators.

The TM 990/189 "University Module" (microprocessor evaluation board) used a TMS9900 microprocessor, and used a top case of a TI-59 as a display and keyboard, but it was definitely not a calculator.