Multiple choice

Which frame is sent first, when one device wants to send data to another device?

  1. An ACK

  2. A poll

  3. A SEL

  4. None of these

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

When one device wants to send data to another device, a SEL frame is sent first. Before sending data, the primary device creates and transmits a select (SEL) frame, which includes the address of the secondary device. Select function is used, when primary device wants to send something to secondary device.