Bally 5000 Plus, Manual

Page: 61 / 388

3 . MPU
-
--
I n t roduct i on ( con t ' d )
I ACK-- I n t e r rupt Acknow l edge S i gna l .
acknow l edges a n I n t e r r u p t .
S i gna l f r om t he 68000 m i c r o p r ocessor t h a t
p r l o r l t y encode r --A c h i p t h a t rece i ves I n t e r r up t s and de t e r m i nes t he h i ghest
p r i or i t y I n t e r r up t to send to t h e 68000 m i c r op rocessor .
se f ec t o r / l n t e r r up t -- ( I ACK4 ) --A c h i p t ha t a l l ows some c h i p s to be used
dev i ces and I s an I n t e r rupt con t r o l l e r
68000 m i c r oprocessor I n t e r r u p t cyc l e .
a s
6800
for
t he
synch ronous--Ope r a t l on s t h a t a r e based on t he s y s t em c l ock f o r t i m i ng . The
6800
c h i p needs t he E s i gna l for t i m i ng .
use r vector number --An 8 b i t numbe r gene r a t ed by t he i n t e r r up t i ng 68000 dev i ce
and r e t u r ned to t he 68000 m i c rop rocessor over d a t a l i nes ,
00-07 .
Vcc--T he 5 . 0 VOC used on t he p r i n t e d c i r cu i t boa r ds .
wor d--A g r oup o f
1 6
b i t s
( 2
b y t e s ) ope r a t e d on a s a un i t .
P r e-ques t i ons
Read t he f o l l ow i ng ques t i ons and w r i t e down any o t h e r que s t i on s .
1 .
Wha t I s a
68000
m i c roprocesso r ?
2 .
Wh i ch ma j o r componen t s a r e pa r t o f wa t c h dog c i r cu i t ?
3 . W h a t I s t he pur pose o f t he se l e c t o r / i n t e r r u p t ( I ACK4 ) c i r cu i t ?
4 . W h a t I s t he d i f f e r ence between EP ROM and RAM ?
5 . W h y I s I t he l p f u l t o unde r s t and " c h i p se l ec t " and " i n t e r r up t c y c l e " ?
6 . Whe r e a r e t he t e s t po i n t s to use t he osc i I l oscope ?
7 . Whe r e does one s t a r t t o f i nd a p r ob l em w i t h t he boa r d ?
8 .
I f a p r ob l em compone n t I s found . whe r e i s t he p a r t numbe r found?
9 . How s hou l d a compone n t be r emoved f rom a mu l t i - l a y e r e d boa r d ?
3-4