Sharp CE-150 - Page 263

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2-3-6. WAIT function
(interfacing with the slow access time memory)
lk causc the Cl'l j access tintc is vt ry fast. 1hc C Plj rn ust be held \\
1
ith th e \V ait signal in
order 10 acce ss a slo\v a ccc ~s tin1c rncn1ory.
l3c tsically. thi: \v ait si gna l is cre at ed by the e xt ernally pr<>v i dc d Co ln'lt <:r. but the J '0 por t
c ontro ll er with the programmable wait time control feature ( L H~S 11 ) is us< d fo r thi s
purpo se. F' or rn orc details of this func ti on. refer 10 the :5CC tio n discu s.si ng the 1
1
0 p or t
co rn ro ller.
S ho wn in the next page is t he c on nect ion of th e CP U with the 110 po rt contro ll er.
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