Sharp CE-150 - Page 403

All and more about Sharp PC-1500 at http://www.PC-1500.info
ADDENDUM
Differences between the PC-1 SOOA and the
PC-1500
Take notice of th c::sc differenc es \Vh en you u se the 111a chint language for the PC -15 00, \.
Page
89
90
91
PC-1500
© Chip select decoder
... and it is used to select chip by
means of S0-4 . S6. S7. 2Y2 and 2Y3.
0 System RAM
Beca us e 1 hc 4- bit X I K byt es TC5514
is used in a pa ir. the da ta b us is
divided
in10 tw (> of DO-D3 and
D4- D7 a nd lhe selec1 si gnal S7 is
con1 n1 on ly shared so as to be
com pa tible with the 8-bit RA M.
Address is within 78 00H lO 7ll FF H
of lhe M EO ar ea which is used fort he
sys tc rn n1 cn1ory area and for t he
fi xed variable area.
© User RAM
h is lhe user RAM for which 8- bi l X
2KB HM6tl6 is used. Add ress
selected by SO is wi lhin 4000H to
47F FH .
4-2-2. Block diagram
4-2-3. Chip select circuit
PC-1500A
© Chip select decoder
. .. and il is used to select chip by
means of S0 -7 . 2Y 2 and 2Y3 . ...
0 System RAM
Address is within 7800H lo 7FFF H
of 1he MEO ar ea which is used for the
systcrn n1enlo ry area. machine
l an gua ge ar ea (7CO I H ~ 7FFFH)a n d
for lhe fix ed variable ar ea.
© Us er RAM
ll is the user RAM for which 8-bilX
2K B HM6 116 is U ~Cd . Address
s cl cclcd by SO- S2 is wi1hin 4000H to
57 FF H.
4-2-2. Block diagram for the PC-
1 SOOA
R efe r to 4- 2-2 diagram for th e PC -
1500A
4-2-3. Chip select circuit for the PC-
1 SOOA
Refer to 4-2-3 circuil fo r lhc PC-1500/\.
1 61
Do not sale this PDF!!!