I still have my original HP-15C from 1987, along with two SwissMicros DM-15L (I had also purchased the official HP reedition HP-15C LE, but one was stolen from work in a burglary, and I resold the other one at a tidy profit, the DM-15L is much better). I also have the official HP-15C iPhone app. And a HP-48GX, HP-33S, HP-35S, DM-42L.
To be frank, it's the only one of my HP calculators I can remember how to program, it's extremely simple, unlike newer models.
HP reedited the 15C manual for the limited edition:
To be frank, it's the only one of my HP calculators I can remember how to program, it's extremely simple, unlike newer models.
HP reedited the 15C manual for the limited edition:
http://www.hp.com/ctg/Manual/c03030589.pdf