Example Program to calculate Factorial

[Dieter]

(02-02-2018 03:28 PM)Gene Wrote:  A real shame HP kept flipping the included conditional tests back and forth back then. A real pain and one of the real cross-model design failures IMO.

That's something I never understood. Was ROM space or the number of available opcodes really so limited that the full set of 12 test commands could not be realized? In the late Seventies the standard set had only eight of them. But while x<0? exists there is no x<y?, and while there is an x≤y? the corresponding x≤0? is missing. Eventually the 41C then featured ten tests, but it still lacked the two for "greater or equal". Weird.

If there really was room for only eight tests HP better had chosen <, >, = and ≠. From these the missing ≤ and ≥ tests can easily be synthesized: the combination x≠y? x>y? is logically the same as x≥y?.

But who cares today?
Tempi passati. ;-)

Dieter