BIGMAC Data Sheet 6 85

Rich Page 6/10/85 BIG MAC DATA SHEET The Big Mac is a high performance Macintosh whic.h can be used as both a Macintosh and as a work station. It is implemented using three 500 gate bipolar ~Jate arrays and one 1200 gate cmos gate array. Display: 1024 x 800 8IW display, 60 Hz refresh, 70Mhz dot rate CPU: 68020 with option for 12M, 16M, and IBM clock rate FPU: 68881 as floating point !coprocessor NIJIU: Custom M~I1U with 4Gb ,address space, 64 entry TLB with 4Kb pages which offers a working set size of 256Kb. Virtual address space is configurable from 16M to 4Gb. The MMU~ supports write and execute protection and <{/ V'iJ;,-u_~ ~ 6 dirty bits for ea-ch-page. - ~"~----./ U . ,c-- I Memory: 2 Mb of DRAM on main logic board using 256Kx1 Separate video memory using 64Kx4 256Kb of ROM using two 1M parts RAM is limited to 10Mb max DMA: 68450 (use 68440 if no 2nd SCC) with support to access the full 32 bit address space. 1/0: Two see chips (ie. four serial ports) SCSI port for internal 20Mb hard disk and external devices Double sided SONY, IWM chip interface, option for 2nd SONY Macintosh compatible sound with SONY sound chip. Front Desk Bus for keyboard, mouse, etc. Real Time ()Iock with battery backup Soft power on/off. Slots: Four 1/0 Slots with access to 32 bit address and data bus Two Memory Expansion Slots Rich Poge 61G MAC LOGIC BLOCK DIAGRAM 6/2/85 68440 CPU DMA 68020 OR 68450 1\1-1\4 FPU FOUR I/O SLOTS 68881 GATE ARRAV-3 SOUND &. VIDEO TIMING 0, 031-D24 ROM'256Kb GATE ARRAV-1A NUX 16 TO 8 VIDEO COUNTER SCC IWM SCSI CLOCK FRONT DESK MMU WITH 64 ENTRV TLB VIDEO RAM (8 - 64Kx4) , GATE ARRAV-1B NUX 1B TO 9 SND COUNTER . . CSC :F109 :F161 70M CPU 7.8M -_ MODE = 1 ~---.. .... GATE ARRAV-4 NUX 20 TO 10 SND COUNTER 35M GATE ARRAV-2 CLOCK GENERATOR MAIN RAM EXPANSION RAM (32 - :>56KxO (32 - 1Mx1)