Octek FOX-II, User Manual

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INSTALLING COMPONENTS
Dip Mem ory Config uration
Memory Bank Memory Location
BANK 0 U 22, U23, U 27, U 28 4425 6
U 1 8, U 1 9 ( pari t y ) 4 1 25 6
B ANK 1
U 24, U25, U 29, U 30 4425 6/4464*
U 20, U 2 1 ( pari t y ) 4 1 25 6 /4 1 64*
*
For the special case of 640K memory configuration, use the
combination of 4464/4164 DRAM size in 'BANK 1' for a more
cost/effective solution.
' U 1 8 , U 1 9'
&
'U 20 , U 21' are t h e par i t y b i t s
f or B ANK 0 a n d B A N K
I
r e s p e c t i v e l y . T h e s e
s o c k e t s c a n b e l e f t b la n k i f pari t y c h e c k i n g l o g i c
i s n o t d e s i rab l e .
T h er e are s e v eral c o m b i n at i o n s o f D R A M
t y p e s y o u may c o n s i d er. S o , a bas i c s y s t e m can b e
e qu i p p e d w i t h f e w er m e m ory a n d l a t e r m ore
m e m or y c a n b e i n s tal l e d w h e n u pgrad i n g t h e
s y s t e m.
As a t y p i cal c a s e , a bas i c s y s t e m c a n b e
e qu i p p e d w i t h 5 1 2 K b y t e m e m ory u s i n g 25 6 K DIP
D R AM a n d t h e n m e m ory s i ze is lat er i n creas e d t o
2.5 M e ga b y t e s b y p ut t i n g a n o t h e r 2 ban k s o f 1 M
S I M M . T h e m e m or y s i ze i s d e t e c t e d au t o mat i cal l y
b y s y s t e m B I O S an d i n d i cat e d d uri n g m e m ory t e s t
a f t er p o w er u p . N o s w i t c h e s o r ju m p e rs are
requ i r e d t o b e s e t f o r t h e m e m ory s i ze an d D R A M
t y p e .
3-6
"
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...
APPENDIX A
SYSTEM BIOS
Al l m i cro c o m p u t er s y s t e m s us e a Bas i c In p u t
O ut p u t S y s t e m . T h i s i s s o f t ware t h at has b e e n
p er m an e n t l y re c ord e d i n a R O M ( R ead O n l y
M e m o r y ) c h i p a n d f u n c t i o n s as t h e bas i c p o i n t o f
c o m m u n i ca t i o n b e t w e e n t h e s y s t e m b oard a n d t h e
r e s t o f t h e c o m pu t e r .
T h e BIO S pro v i d e s an o p erat i o n a l i n t er fac e
t o t h e s y s t e m a n d re l i e v e t h e program m e r fro m
w orr y i n g a b o u t t h e c h arac t e r i s t i c s o f h ard ware
d e v i c e s .
T h us, h ar d ware m o d i f i cat i o n s a n d
e n h a n c e m e n t s b e c o m e tran s pare n t t o u s er's
progra m s , ac c e s s to B I O S i s t h r o u g h t h e program
i n t erru p t s o f t h e 8 0 28 6 m i cro pro c e s s or.
Eac h
B I O S e n try p o i n t i s avai l ab l e t h ro u gh i t s o w n
i n t e rr u p t.
U p o n y o u t ur n o n t h e p o w er o f y o u r F O X -II
s y s t e m, t h e s y s t e m w i l l go t h ro u g h a s e l f - t e s t
ro u t i n e w h i ch c h e c k s a l l o f i t s i n t e rnal d e v i c e s .
C o m p l e t e t e s t i n gs w i l l b e carr i e d o u t o n t h e C P U ,
bas e 64 0 K R A M, e x t e n d e d R A M, R O M, s y s t e m
b oard , C M O S m e m or y , v i d e o c o n t ro l l ers, paral l e l
a n d s er i al s u b s y s t e m s , f l o p p y a n d f i x e d d i s k
s u b s y s t e m s a n d t h e k e y board .
W h e n t h e s e l f - t e s t i s c o m p l e t e d , t h e s y s t e m
w i l l s earc h f or t h e D O S ( d i s k o p e rat i n g s y s t e m )
s y s t e m f i l e i n d r i v e A . I f n o s y s t e m d i s k e t t e i s
p u t i n d r i v e A, i t w i l l c h e c k t h e f i x e d d i s k ( i f
i n s ta l l e d ).
A-1