by - 7-digit serial numbers were used until January 1994, when TI switched to using 8-digit serial numbers.
- The first two digits of a serial number change at least once a month, and rarely more than once a month. An example of the latter is March of 1994, when serial numbers 15xxxxxx I-0394L and 16xxxxxx I-0394M are both present in that month of production.
- The first two digits of a 7-digit serial number directly corresponds with the month of manufacturing, e.g. 05xxxxx I-0593, and 06xxxxx I-0693.
- The last five digits of a 7-digit serial number do not appear to be in chronological order, however I do not have a lot of concrete evidence to show what those digits may actually mean. The rapidness of the ROM version changing in the I-0593 TI-82s provides an excellent method of gathering relative production dates, assuming that TI upgraded the ROM chips' firmware in chronological order.
- Even within very small (n<3500) changes in serial number, significant changes in hardware revision and ROM versions can be observed. Additionally, as per the previous point, these changes bear no particular order: I have observed the order 12.0 --> 8.0 --> 10.0 --> 9.0 all within the space of 6000 serial numbers, sorted here in ascending order of serial number (0605463, 0608697, 0615716, and 0623045, respectively).
Furthermore, I have made the following tentative (and possibly incorrect) observations:
- All hardware versions between A and F were produced in less than a month. HW pre-A and HW-F were both produced in June 1993.
- Starting with HW-E, ROM chip+version and hardware revision are correlated.
- Calculators with HW-E and HW-F have ROM 10.0. Before 10.0, the hardware revision is not labeled.
- HW-F is a version of HW-E that uses a mask ROM instead of an OTP-ROM, and is produced about a month later (after HW-H, oddly). See this post for more details.
- Calculators with HW-G have ROM 11.0.
- Calculators with HW-H have ROM 12.0.
- Calculators with HW-I have ROM 15.0. This makes the existence of ROMs 13.0 and 14.0 unlikely.
- HW-J could be ROM 16.0 on a OTP-ROM chip. I will investigate HW-J after I complete my work with previous HW versions.
As of 18 August 2015, this is the list of all possibly known OS versions:
- 1.0 (referenced at United-TI, subsequently owned by CVSoft, dumped)
- 3. (owned by CVSoft, previously unknown, subsequently listed at Ticalc, dumped)
- 3* (listed at Ticalc, not dumped)
- 4* (listed at Ticalc, subsequently owned by CVSoft, dumped)
- 7* (listed at Ticalc and Datamath, mostly compatible with JASS and OS-82 assembly shells, owned by CVSoft, subsequently dumped)
- 8.0 (listed at Ticalc, owned by CVSoft, subsequently dumped)
- 9.0 (previously unknown, owned by CVSoft, subsequently dumped)
- 10.0 (listed at Ticalc and Datamath, owned by critor and CVSoft, found on eBay, dumped)
- 11.0 (listed at Ticalc, owned by critor, dumped)
- 12.0 (listed at Ticalc, formerly owned by Datamath, owned by CVSoft, first dumped by critor)
- 15.0 (listed at Ticalc, found on eBay, owned by Adriweb and CVSoft, dumped by Adriweb
) - 16.0 (common version)
- 17.0 (common version)
- 18.0 (common version)
- 19.0 (common version)
19.001 (reported at ticalc, possibly typo)19.002 (reported at ticalc, possibly typo)- 19.006 (common version, found on Parcus models)
Software Bugs in Pre-16.0 ROMs
| ROM Version | Plot1( Bug |
| 1.0 | No |
| 3. | Yes |
| 3* | Untested |
| 4* | No |
| 7* | No |
| 8.0 | Yes |
| 9.0 | Yes |
| 10.0 | No |
| 11.0 | No |
| 12.0 | No |
| 15.0 | No |
Additions
As I find new information and acquire more rare TI-82s, I will update this information to factor in the new information.
- PCB images of the TI-82s that I own are available; click here to jump to the relevant post. Hardware versions pre-'A' (three of them), 'E', 'H', and 'Q' are shown.
- The ROM routine table has changed in length throughout various ROM versions, and provides indication of the existence of ROM 9.0: click here to jump to the relevant post.
- The first ROM version found to appear with a mask ROM is ROM 10.0, at HW-F. HW-E is the OTP-ROM-based counterpart. Click here to jump to the relevant post.
- The *-series of ROMs (3*, 4*, 7*) were entirely produced in May 1993, and do not have a hardware revision labeled. It is very well possible that the *-series is a bugfix of the 'normal' ROMs; see the bug list.
I'd like to give a big thanks to critor for his support, work, and progress on this task. Without his support, much of this work would have been impossible or otherwise not completed. Furthermore, my original inspiration to find the remaining TI-82 ROM versions was critor's work with ROMs 10.0 through 12.0. Thank you.
