| This clock is based on a 480x360 tFt Color Graphics display which is sized and configured to be an Arduino shield. It has a built-in micro SD socket which is directly connected to pins 10 - 13.
It is designed to be controlled by a UNO Arduino, and in fact works easily with one.
However, since it uses all of the UNO's pins less 1,2,A5 and the I2C it is not practical to use it with a UNO.
The step-up is to substitute a Mega, a 2560 rev 3, which has ample pins and memory. The display will mount as a shield on a Mega, but this prevents using the SD because the Mega uses pins 50-53 instead of pins 10-13 for its SDI protocol. The display is molded, so to isolate these pins a general-purpose proto shield was intersposed. Its pins 10-13 are cut off. For convenience, the SDI MOSI,MISO and SCK pins on the display are actually wired in this shield to the ICMP connector, which in the Mega is directly connected to pins 50-52. Pin 53, the SS pin, needed a jumper to the shield.
To provide manual control, a 16-position rotary Grey-Code selector and a DPDT monentary switch are provided.
The Clock has capabilities in addition to displaying time, date, and the environmental outputs of the BME688 which are not germane to this discussion.
These are the photos of the finished clock.
Here are the clock circuit diagrams.
Here is the Arduino program.