AT&T 3B2/300 Technical Reference Manual page 261

FUNCTIONAL D E S C R I P T I O N - - - - - - - - - - - - - - - - - - - - - - - -
VERSION 3 COMPUTER
CABINET
r--------------------,
FLOPPY
DISK
DRIVE
VCACHE
(OPTIONAL)
PBUS
(CARDS
OPTIONAL)
r-------------
----,
1 . - - - - - ,
: CONSOLE
6 A : .
.....-----1i
L __
N_O_T_E_l _ _ ~
CONTTY
9 :
~---------------~
SYSTEM BOARD
MISCELLANEOUS
LOGIC CIRCUITS,
ROM, TIMERS,
NVRAM, ETC.
INTEGRAL
CONTROLLERS
NOTE 2
DIRECT
MEMORY
ACCESS
CONTROLLER
ENHANCED 1/0 BUS
SLOT 12
SLOT 11
SLOT 10 SLOT 9
SLOT 8 SLOT 7
- - ffe~I;I; ~ - -
SLOT 6
SLOT 5
SLOT4
SLOT 3
SLOT 2
SLOT 1
(NOTE 6)
MICROPROCESSOR,
MEMORY
MANAGEMENT
UNIT, AND
________ .J
MATH DUAL PORT
ACCELERATION DYNAMIC RAM
UNIT CONTROLLER
L----------------------------------.J
NOTE
2
BUBUS
(CARDS
OPTIONAL)
.----6------.
&
NOTE3
~
r
POWER SUPPLY ASSEMBLY ,
+SV, +12V, -12V
r
RANDOM ,
: ~~~JiY
I
RAM
O
I I
RAM 1
I
l
ON/STANDBY
SWITCH
I
CARDS
(NOTE 5) - - - - - - - - - - - - - - - - - - - - - - - - -
I
l
I
RAM2
I I
RAM3
I
l
L-----------------------------------.J
NOTES:
1. UNBUFFERED 32-BIT ADDRESS BUS AND 32-BIT DATA BUS.
2. BUFFERED 24-BIT ADDRESS BUS AND 16-BIT DATA BUS.
3. 32-BIT DATA BUS PLUS BYTE PARITY.
4. 3B2/500 COMPUTER HAS 7 SLOTS. OTHER VERSION 3 COMPUTERS HAVE 12 SLOTS.
RESET
SWITCH
5. 3B2/500 COMPUTER HAS 2 MEMORY SLOTS. OTHER VERSION 3 COMPUTERS HA VE 4 SLOTS.
6. SLOT 1 IS NORMALLY OCCUPIED BY THE SCSI HOST ADAPTER CONNECTED TO THE
INTERNAL HARD DISK DRIVE(S) AND CARTRIDGE TAPE DRIVE (IF EQUIPPED).
Figure 3-2: Version 3 Computer - High-Level
Functional Block Diagram
3-8 TECHNICAL REFERENCE MANUAL
POWER
SUPPLY
SET
FAN
ASSEMBLY