Is HCE bi-directional communication possible?

Question

According to this solution, by using the sample app for card emulation and card reader:

1. we can setup a HCE card (card emulation) in "Device A", and send the data to a reader (card reader) in "Device B".
2. What if I want to continue this process by sending a "amount" from "Device B" back to "Device A"? Is this achievable?

Note: Both devices are 4.4+.

Answer 1

HCE use ISO-7816-4 standard so you communicate with APDU

APDU process is: Reader send command (with optional data) to card. Card respond (with optional data) to reader.

Card could not send command to Reader.