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What is the essential difference between citta and vinnana?
I refer to this text of Ajaan Nanasampajanno in his book 'Arahatthaphala-The Path to Arahantship' p. 53:
'The citta is the essential knowing nature at the core of our being. It consists of pure and simple awareness: the citta simply knows. Awareness of good and bad, and the critical judgments that result, are merely conditions of the citta. Et times, their activities may manifest as mindfulness; at othet times, as wisdom. But the true citta does not exhibit any activities or manifest any conditions at all. It is simply a state of knowing. The activities that arise in the citta, such as awareness of good and bad, or happiness and suffering, or praise and blame, are all conditions of the consciousness that flow out from the citta. Since they represent activities and conditions of the citta that are, by their nature, constantly arising and fading, this sort of conscious awareness is always unstable and always unreliable. Understood in this way, sanna, sankhara and vinnana are all conditions of the citta.'
Is this citta—pure and simple awareness—the same as what is mentioned in Bahiya's teaching (Udana 1.10): ‘In seeing there is mere seeing, in hearing mere hearing, in smelling mere smelling, in tasting mere tasting, in touching mere touching, and in cognising only cognising.'