[ ] <120> = File ready F_FR_NA_1
[ ] <121> = Section ready F_SR_NA_1
[ ] <122> = Call directory, select file, call file, call section F_SC_NA_1
[ ] <123> = Last section, last segment F_LS_NA_1
[ ] <124> = Ack file, ack section F_AF_NA_1
[ ] <125> = Segment F_SG_NA_1
[ ] <126> = Directory F_DR_TA_1
A4 Telecontrol Interfaces P634
P634/EN M/R-42-A // P634‑311‑653 A4-7