01-12-2016, 09:48 PM
Hi everybody,
I have in front of me an HP-16c, which behaves oddly.
The good:
First of all, both self tests run without errors. But while using the device, the following happens:
- I calculated 15 minutes of random integers. No problems. HEX/DEC/BIN/OCT work like a charm.
- I noticed that converting to DEC takes a while (>3 seconds), while BIN/DEC/OCT are shown almost instantly. Is that normal?
- Floating point calculation works. I calculated 10 minutes of random numbers and tried most functions.
The bad:
- I cannot change the word size in integer mode. If I type "8 WSIZE" the calculator display blanks and stays blank. If I pull out a battery, and wait a while, and put it back in, random things happen - blinking display, or wrong calculations (3+3=2.5) or such. I can bring it back to function with a memory clear (ON+MINUS).
- If I go into PRGM mode and clear the programs, the calculator correctly shows "000-". If I start to type in programs, it always starts at line 85, and if I continue to program, the line number wraps around after line 91:
The interesting thing is, the program works anyway: if I now press R/S, the display shows "12345 d" which is correct as the word size is 16.
Also, some key codes are shown wrong:
Most keys including the gold f-shift are wrong as far as I can tell (though the program seems to work fine as far as I tested, but I guess that would not work for longer programs).
Any ideas? My guess: The RAM is broken or desoldered, as the self test runs fine I guess that the ROM should be ok (though I dont know what exactly is tested in the self test).
I have in front of me an HP-16c, which behaves oddly.
The good:
First of all, both self tests run without errors. But while using the device, the following happens:
- I calculated 15 minutes of random integers. No problems. HEX/DEC/BIN/OCT work like a charm.
- I noticed that converting to DEC takes a while (>3 seconds), while BIN/DEC/OCT are shown almost instantly. Is that normal?
- Floating point calculation works. I calculated 10 minutes of random numbers and tried most functions.
The bad:
- I cannot change the word size in integer mode. If I type "8 WSIZE" the calculator display blanks and stays blank. If I pull out a battery, and wait a while, and put it back in, random things happen - blinking display, or wrong calculations (3+3=2.5) or such. I can bring it back to function with a memory clear (ON+MINUS).
- If I go into PRGM mode and clear the programs, the calculator correctly shows "000-". If I start to type in programs, it always starts at line 85, and if I continue to program, the line number wraps around after line 91:
Code:
Key Display
P/R 000-
1 085- 1
2 086- 2
3 087- 3
4 088- 4
5 089- 5
6 090- 6
7 091- 7
8 085- 8
The interesting thing is, the program works anyway: if I now press R/S, the display shows "12345 d" which is correct as the word size is 16.
Also, some key codes are shown wrong:
Code:
Key Display
x<>I 085-000 72 (Should be: 001- 42 22)
x<>y 086-000 34 (Should be: 001- 34)
CLX 087- 43 35 (display is correct)
Most keys including the gold f-shift are wrong as far as I can tell (though the program seems to work fine as far as I tested, but I guess that would not work for longer programs).
Any ideas? My guess: The RAM is broken or desoldered, as the self test runs fine I guess that the ROM should be ok (though I dont know what exactly is tested in the self test).