TI59 Diagnostic forensics

[Pjwum]

In a recent Thread member twoweims asked for a source for TI59 magnetic cards. During the discussion he mentioned a Diagnostic routine which is included in the US marketed version but not in Europe. Twoweims was so kind to send me a copy of the Diagnostic card.

Basically it calculates the error of some seemingly arbitrary functions:

\begin{equation}
error = pol(rec(5 < 30)) - \sqrt{896 + 4} + \frac{\pi^2-fp(\pi^2)}{3^2}-1
\end{equation}

then checks if this error is within a certain limit:

\begin{equation}
error \cdot 10^{10} < 1 ?
\end{equation}

The TI59 calculates 0.7 and signals an ok.

I was curious how other calcs of the same vintage would respond to this task. A 41CV and a 33C both showed an error of zero. But also both have less internal precision (10 digits) than the TI (12 digits). But the same calculation with a 48G and a 42s (12 digits) also resulted in an exact zero. Good job, HP.

The other facets of the Diagnostic card are:
- reading the card tests I/O-chip, amplifier-chip, magnetic head coils and mechanics
- maximizing the programme by inserting lots of zero-steps and adressing the lowest and highest storage register tests the RAM-chip

Patrick