#FRIDEN CALCULATOR EBAY DIRECTIONS SOFTWARE#

Many times, during the time she was watching us, my 'Auntie', as I called her, would be hammering away at the Friden, working on generating the charts. When my Mom had errands to do, my Godmother would regularly babysit me and my little brother. My Godmother would take the worksheets generated by her husband in the field and use the Friden to perform the math necessary to generate a final chart giving the total number of pounds of milk in the tank based upon a 'dipstick' reading. The calculator that was used to grind through the interpolation process to generate these dairy tank charts was a Friden STW-10. My parents were very good friends with these neighbors, and in fact, they were named my Godparents when I was born. Back in the early '60's, when I was just a child living in Seattle, Washington (my birthplace), one of our neighbors owned a business which involved use of a calculator to generate dairy tank calibration charts. I used standard devices that could be sourced anywhere.Friden Model STW-10 Electro-Mechanical CalculatorДЄ machine identical to this has a special place in my personal history. The reason that it was commissioned was that Sinclair could no longer source the chips used in the original Super Settler.

#FRIDEN CALCULATOR EBAY DIRECTIONS SOFTWARE#

I spent many sleepless nights with the programming as it was actually programmed directly in machine code, and I did not have access to any form of assembler software in those 'I designed this calculator for Silicon Express and hadДЄccess to the original algorithms from Sinclair.

The case is made of wood and sheet metal, rather than plastics mouldings which are expensive to get into production.Д¬hris Beasley has kindly provided information about the design of the Super Settler II which throws light on it:.

The specialised calculator functions are obtained using a Z80 type microprocessor with program held in a 2732 EPROM, with 4 KBytes capacity.

Use of large LED displays in a desktop calculator is very unusual, but by this time large 7-segment LED displays were cheap and very easy to interface to integrated circuits - easier than vacuum fluorescent displays.

This highly specialised calculator was a bespoke design and has features suggesting that it was manufactured in small quantities. Generally had vacuum fluorescent displays and one main integrated circuit which performed the calculating functions. By this time in their development standard desktop electronic calculators were manufactured in tens of thousands, and

Manufactured by Silicon Express, Silicon House, Rothley, Leicestershire, England.ДЄlthough dating from as late as about 1982, this calculator is included due to its interesting electronics. The integrated circuits are here date coded to 1982. This stores up to 32 Kbits (= 4 KBytes) of program. The program to produce the calculator functions is stored in a 2732 EPROM (Erasable, Programmable, Read-Only memory).

The circuit is based around a Nippon Electric Company (NEC) D780C which is a fully compatible version of the original NMOS version of the ZILOG Z80 micro-processor. Display is 8 digits, red LED, with an additional window for a 7-segment display.

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