CASIO HQ-31, strange calculator/calendar

[xerxes]

(04-26-2022 05:29 PM)Dan C Wrote:  Now when i have set the date to 22-04-26, the column marked in the calendar is 2,9,16,23,30.
And these must be the days in the month?

The marked column should show the sundays, but I assume that you have set the date to April 1922. Have you tried to set the date as "20220427"?