Specifying input parametersUsing LCDS Print Description Language 2-5Forms control buffer (FCB) and vertical format controlprocessingThe 3211 and 4245 forms control buffer (FCB) defines channelpositions and forms length. You may restrict the forms controlbuffer information by accepting or suppressing the normalprocessing of host transmitted FCB input. To suppressprocessing of FCB input, specify FCB=IGNORE in the LINEcommand.The vertical format unit (VFU) in the JSL and the FCB sent fromthe host interact as follows:• When you start a job, the VFU table and its associatedBottom of Form (BOF) in the JDE become active.• If no VFU is specified in the JDE, the last FCB sent from thehost becomes active.• When a DJDE is used to change a channel assignment, anyprevious assignments to the channel being changed aresuspended until the end of report. At the end of report, DJDEchanges are discarded and the last active FCB or VFUbecomes active again.• When operating system software is reinstalled or upgraded,the FCB saved on disk is reinitialized to the length of 66 lineswith the following channel assignments:The default corresponds to the STD2 default supplied byIBM.• If a Print and Skip to Channel command is sent for anundefined channel, the system executes a Print and Space 1command.Print positionindexing (non-U.S.markets only)The print position indexing (PPI) byte determines whether linesshould be shifted horizontally. If either the sixth bit or the seventhbit of the first byte in the loaded FCB is on, the byte is a PPI byte,and the lower five bits indicate the amount of shift.For example, if the first byte is 0 x 48 (01001000), each line shiftsseven (0x48^0x1f -1) character spaces to the right (the sixth bitindicates that the shift is to the right).Table 2-1. Default channel assignments made at installationChannel 1 2 3 4 5 6 7 8 9 10 11 12Line 4 10 16 22 28 34 40 46 52 58 64 66
