Advanced Micro Devices - FTP

CHAPTER 2System Bus InterfaceJ015014013012~ ~~,W'~,'~,'~,'~~~,'~0000111122223333,.~~~S01615QPOM4 1413lane 12BY·PIXEL011010D9~} N ,." .. ~ ,."W ,.,,'N ,.,,'r! OOOOP"1122223333 QPOM3~O~rl'016Ian. 81110DB$ I.}~~~~~~~~~~~~~~~~07D605D4~ 0000111122223333~~P,16QPOM203 QPOMl020100XCVRDENot.: ~ - bk lor p~.1 x from plane y.Figure 2.1-6a By Pixel (Output Block) Read - First CycleThere is no reasonable way to change this relationship;everything else will have to match. To make lID by-pixelconform, one must wire the by-pixel data transceiver asshown in Figure 2.1-6, "By Pixel Read". Also see Chapter13 of the QPDM Technical Manual, ''The RelationshipBetween Data Bits and Pixels." It should be noted herethat only pixels that are 16 planes or less can be processedin one pass; deeper bit planes would requiremultiple passes.Other Synchronization ConcernsThe synchronization of getting new words out of theinstruction FIFO and reading and writing the data ex·change FIFOs use the MATIN and MAToUT pins. TheMATouTpins of allthe QPDMs are ANDed together. Thiscomposite signal goes HIGH only when all the QPDMsare ready to begin the next instruction. All QPDMssample the composite MAT OUT signal at the MATIN input.From an interface standpoint, allthat is required isto ANDthe MAT OUT pins and connect the composite signal to theMATIN pins. The AND is done in PAL device QPDM2.In a similar fashion, the TSYNoUT and TSYN IN pin combinationis used to synchronize the bit map display memorybus activities. The same hardware considerations discussedin the preceding paragraphs apply. The AND isdone in PAL device QPDM1. Please note that even in asingle QPDM system MATIN and MAToUT must be tiedtogether, as are TSYNoUT and TSYNIN"2.1.3 Hardware OverviewRead CyclesThe multiple QPDM read is shown in Figure 2.1-7, "QuadQPDM Read TIming". The situation is Sightly more2-13