AFAIK it's the same, ~21 Million BCHA = ~21 Million * 1,000,000 XEC
XEC is like Satoshi (bits to be precise), nothing change except the notation or how you write.
1 BTC = 100,000,000 Sats
1 BCHA = 1,000,000 XEC
7. What is the base unit of eCash?
eCash uses ”bits” which make it easy to send small payments because you no longer have to handle unwieldy decimal places. For instance, instead of sending 0.00001000 bitcoins (which was the base unit used by BCHA), you’ll simply send 10 bits!
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