SEPA Instant rulebook is available on the European Payments Council website.
Detailed documentation including ISO20022 field level specification is available on the European Automated Clearing House Association (EACHA) website. (Annex III Administration Messages contains the specification of ping (echo messages) mandatory in the GIROInstant implementation):
The European Central Bank provides Documents on TARGET Instant Payments Settlement (TIPS).
The rulebooks became available for the public.
The central bank of Hungary (MNB) has publications available in Hungarian:
The law regulating fund transfers in Hungary:
SEPA Instant mandates to use old versions of the documents . They can be found in the archives.
The current versions can be found here: