Board Descriptions A - 14 OF 5300/5600 Serv Man, P/N 59278301(4) 300 bps Send ModeFigure A2.2.4 shows the 300bps send protocol signal routeIn G3 communication, this is the route of the procedural control signals (pre-message, post-message phases etc.) at 300bps.The protocol send data is read into DRAM in the sequence the contents of varrious data stored inthe FLASH memory area in advance under the control of CPU. The contents of the frame hasbeen edited on the DRAM by CPU and sent to MODEM via CPU. HDLC (high level data linkcontrol) frame of the data is structured by the modem and converted to serial data in synchronywith the modem’s DCLK (data clock). After modulation, the protocol signal is output from “S” ofthe modem and sent to the telephone line L1 and L2 via the transformer T1 of NCU.
