casio aq-1500

when power consumption was so low it was possible to power the LCD display continually for more than a year, casio experimented with putting the time and date in calculators. this model is typical of such types. there is also a stopwatch that works to 10ths of seconds.

in addition to time and stopwatch features of the aq-1000, this model also has the date. unfortunately there is no way to perform time or date arithmetic which is a shame. the alarm feature of the older aq-1000 is no longer present.

the method of entry to set the time and date is rather quirky. enter a four digit number and press "set" to set the time (24h) or enter a six digit number and press "set" for the date (yymmdd). unfortunately dates with years starting with 0, like 02, cant be entered. however, if they could, presumably they would interpret as 1900's not 2000's.

i tried to fool it as follows, 991231 SET 2359 SET, then wait 1 minute. the machine goes blank for a while eventually reporting the correct time but results in "E" for a date request.