Electronic device and display system

An electronic device comprising:

• a semiconductor device,
• wherein the semiconductor device comprises a CPU, an accelerator, and a memory device,
• wherein the CPU comprises a scan flip-flop circuit and a backup circuit electrically connected to the scan flip-flop circuit,
• wherein the backup circuit comprises a first transistor,
• wherein a layer where the backup circuit is provided is stacked with a layer where the scan flip-flop circuit is provided,
• wherein the accelerator comprises an arithmetic circuit and a data retention circuit electrically connected to the arithmetic circuit,
• wherein the data retention circuit comprises a second transistor,
• wherein a layer where the data retention circuit is provided is stacked with a layer where the arithmetic circuit is provided,
• wherein the memory device comprises a memory cell comprising a third transistor, and
• wherein the first transistor to the third transistor each comprise a semiconductor layer comprising a metal oxide in a channel formation region.

A display system comprising:

• a first electronic device;
• and
• a second electronic device,
• wherein the first electronic device comprises a first display portion, a first wireless communication means, and a first sensor,
• wherein the second electronic device comprises a second display portion, a second wireless communication means, and a second sensor,
• wherein, when the first wireless communication means and the second wireless communication means are linked to each other, the first electronic device and the second electronic device are connected to each other, and
• wherein the display system is configured to display any one or more of augmented reality, virtual reality, substitutional reality, and mixed reality on the second display portion based on any one or more pieces of information input to the first sensor and the second sensor, and to operate an image on the second display portion based on the information input to the first sensor.