Sharp PC-1500 - Page 47

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2-4-7. CPU control instructions
@ SEC (SEt Carry)
Sets t he carry fl ag .
. o change takes place
in fl ags.
• Format
S EC
@ REC (REset Carry)
Re s ets I he c<1r ry flag .
•Ope ration
1 -C
No c ha nge ta kes place in flags.
• Fo nna t
REC
@ CDV (Clear DiVider)
•Op eration
0 - c
Cle ars th e i nt ernal di vid er. In o th er words. si nce the CPU cl o ck is s up pli ed through the
d iv ide r. it makes cl ock re se t by the CDV instruction.
• Fon nat
CDV
•Op eration
0 - divi de r
@ ATP (Ace To Port)
The cont en ts of the accumulator are se nt on the da ta bus. As th e cl ock P 4> is se nt out
from the
CPU at this moment. it may be used for the clo ck of the latch IC to compr is e
an out
pu t port.
No change takes pl a ce in fla gs .
•F ormat
ATP
C lock P <ti- -~
•Op eration
H
~-- --- L
H
Data bus - - ----< )- -- - - ( Hi gh imped a.nc e)
"l'.- ---- J l
Coni ents of accumula tor a re sen1 ou1
Address b us
~ -- H
~-- L
Conlf~ n 1 s ol the X ( e91s uu are se n1 out
H
0 D ------------- - - L
NOTE: Though data is ou tput with hi gh state of OD (ou tp ut disabl e) du ring memory wri te. OD
is l ow sta te in the case of the A TP instructi on .
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