Details:

The TRS 1300P is a programmable calculator.  That is what the ‘P’ stands for.  It was introduced in a period during which changes took place very rapidly.  It contains one large  calculator-IC  (NEC D1200C), some small scale integrated circuits and some discrete components.

The programming feature allows storage of a tiny 14 steps program. The machine uses the Grand Total register for this purpose.  Digits and GT (halts a running program) take one step, other operations take two steps. The  original manual contains some programming examples, one of which is entering the current date. It can then be printed with a singe key-stroke. Other examples include the calculation of an average out of a sequence of numbers and a tax calculation.  

The manual that came with the machine also contains a supplement with another eight programming  examples.

Usage:

Addition/subtraction:

Use the “+” and “--” key to add to the Total register.  Using the “M”  version stores the result in Memory.

Multiplication:

Enter 1st number, push the “X”-key, enter the 2nd number, push the “=” key.

To add the result to the Total register use the  “+” key  in stead of  or after the “X”-key.  To subtract use the ”--” key

To add/subtract the result in Memory use the  “M+” / ”M--” key

Division:           

Like multiplication as described above, but using the “:” key in stead of the “X” key.

Function of some keys, switches etc.

• “CE” clears an erroneously entered number
• “C”  clears an erroneously entered number and also the last entered (not yet executed) function (e.g. “X”)
• “T” prints the content of the Total register, adds its value to the Grand Total register and then clears the Total register
• “GT”  acts differently dependant on the mode switch GT/PW/PR:

1.  GT: the content of the Grand Total register and  the related item counter are printed. The register and counter are then cleared.
2. PW:  halts a running program if “GT” is encountered. It allows the user  to enter a number or function.
3. PR: starts execution of a stored program

• “<>/#”  prints a number without using it in a calculation or -if you didn’t enter a number- an intermediate Subtotal
• “IC” prints the Item Counter (number of executed operations)
• “√” calculates the square root of an entered number.
• “%” determines 1/00 of the entered value. Can be used to add or subtract from the Total register.

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Serial number:

Built in:

Functions:

Power:

Market-introduction:

Production until:

Price:

L083650

Approx. 1977

Addition, Subtraction, Multiplication, Division, Square Root, Limited programmable

220V

1977 ? (It does not appear in Büromaschinenlexicon)

1978 ?

Approx. DM 300 ?  
(The Brother 122PDR seems to be a similar calculator but without programming feature.  It was priced   DM. 269 in 1978)