Digital Equipment VAXstation 4000 90, Service Information

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System Overview,
Continued
CPU
Components Table 1–1 lists the major hardware components found on the
KA49 CPU module.
Table 1–1 Major Components
DC246 Central processor NVAX
Cache RAMs 256-KB Bcache —–
DC243 NDAL to CDAL I/O bus interface chip NCA
DC244 Main memory controller, with ownership
bit control NMC
NCR 53C94 Advanced SCSI controller —–
DC541 Ethernet interface SGEC
—– 32-Byte network address ROM socketed
AM79C30A Sound generator —–
XC3090 CDAL to EDAL chip CEAC
XC4005 SCSI Quadword FIFO chip SQWF
DC7085 Quad UART DZQ11
DC509 Clock CCLK
DS1287A Time-of-Year clock TOY
Firmware ROMs (4) 512 KB; each 128 KB by 8, FLASH
programmable —–
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