EEVblog #1102 - Casio FX730P 1980's BASIC Scientific Computer - Page 1
Forum section: electronics / general

author: EEVblog
author_rank: Unknown
timestamp: July 07, 2018, 11:59:00 pm
content: Inside a classic 1987 Casio FX-730P Scientific Calculator / BASIC computerThanks to the Defpom:https://www.youtube.com/user/TheDefpomwho dropped by the EEVblog lab

author: MBY
author_rank: Regular Contributor
timestamp: July 08, 2018, 03:05:27 pm
content: I have a few Casio and Sharp "BASIC"-calculators in this form factor. They are very useful indeed and even rival HPs in usability. But, for some reason, Casio screws things up with their "modes" and numbered program. The Sharps are much better in this regard, integrating the calc function with the programming function by assigning programs to keys (in a better way, that is. Of course the Casio also has program assigned to keys).I don't think the BASIC is related to Microsoft, at least the Sharp models (even if I have a few Casio BASIC-calcs I don't use them often enough to remember), but there is a way to test this. One *very* good feature is computable DATA-statements. In Microsoft BASIC (all of them), all DATA-lines can hold is constant numbers or text. In Sharps (and I suspect, Casios) BASIC, you can have a formula in a DATA-statement. This means that things like a unit converter can be programmed in very elegantly. Another quirk is that "LET" is mandatory in assignments after IF-statements.As far as I remember, I have seen three different clock speeds in those calculators, 900 kHz, 1,25 MHz and "don't-remember-but-over-1 MHz". The irregular hole on the back side is either for docking with a thermoprinter/tape station or a missing tilting bail. Most likely for docking.These (especially Sharps physically smallest models) are among the most useful calculators ever made, even rivaling HPs Voyage- and Pioneer series (which may be the greatest calculators known to man).It's a good thing you didn't do an destructive tear down! The FX730P will still give years of useful life!

author: Bicurico
author_rank: Super Contributor
timestamp: July 08, 2018, 04:29:38 pm
content: The basic is from Casio and it is stored in secured form so that you cannot just dump the ROM contents. This is why there are no emulators for these fine calculators.This polish power user has dumped the ROM of the PB1000 and PB2000 and naturally made emulators. The same for other palm computers:http://www.pisi.com.pl/piotr433/index.htmThe springs are to produce the beep sound and having two means that two different tones can be produced.The black thing on the back is to tightly connect the calculator to the printer/tape add-on.The most popular calculators of this series are the FX850P and FX880P. These are still actively being used and sold for 100 to 200 Euro on eBay.Most common issue is the LCD flat cable which often fails and causes missing lines on the display.What is appealing on these machines is how simple and quick it is to program an algorithm to calculate something.Today's calculators may have much more CPU power and offer so many more functions, but most are crippled to death by exam regulations:- no qwerty keyboard- no Basic or some custom language which you need to learn first- very complicated GUI- etc.I own a good collection of calculators and yes, I prefer my HP 50G as my every day calculator. But I do cherish the Casio FX-7xx and 8xx. I am looking for ages to get my hands on a PB1000 and PB2000, but they are rare and expensive.Regards,Vitor

author: MBY
author_rank: Regular Contributor
timestamp: July 08, 2018, 07:39:49 pm
content: Bicurico, if I'm not mistaken, there were one or two Casio models programmable in C, not BASIC. Do you know their name or status today?

author: Bicurico
author_rank: Super Contributor
timestamp: July 08, 2018, 08:35:33 pm
content: That would be the mentioned PB1000 and PB2000.The PB2000 could use cartridges and the BASIC one would add this language to C.In the link above you can download emulators of these machines together with the images of the modules.Regards,Vitor

author: Bicurico
author_rank: Super Contributor
timestamp: July 08, 2018, 11:56:27 pm
content: I stand corrected. In this case the springs are to facilitate the removal of the back cover.Sorry.

author: SilverSolder
author_rank: Super Contributor
timestamp: July 10, 2018, 12:27:23 am
content: LOL brings back memories, I had one of these in the 80's. Had it programmed with probability calculations for Bridge hands!You could do a lot with a little, back in the day. (you had to!)

author: BravoV
author_rank: Super Contributor
timestamp: July 10, 2018, 01:05:37 am
content: That IO connector is for cassette tape interface for saving/reading the saved programs.