... wire E/M, 4 wire E/M, telegraph, V.35, V.24/V.28, 64K, N×64K, Ethernet subchannel card. ... test and signaling test for analog interface, functional test for data interface, functional tests of A/B ... contains 4 ch asynchronous RS232 data interface, conforms to ITU-T V.24/V.28 standard-RS485 data card: ... channels asynchronous RS485 data -FV.35 card: contains 1 ch synchronous V.35 data of N×64Kbps data rate ...