----SHARP---- SERVICE MANUAL CE-155 WWW. PC-1500 .INFO SHARP CORPORATION Do not sale this PDF !! ! All and more about Sharp PC-1500 at http://www.PC-1500.info MODEL CE-155 8KB RAM MODULE (PC-1500 OPTION) File this manual into the sen·icc manual .. PC-1500 & OPTl0:-1 .. Do not sale this PDF !! ! All and more about Sharp PC -1 500 at http://www. PC-1500.info 1. Outline It is the option 8KB RAM that can be 11sed for the PC· I SOO. 2. RAM address Chip select signal 3800 RAM I From Y 7 (7-pin) of TC40H138 . 13800 - 3FFF) 4000 On PC·I SOO 4800 RAM2 SI Cfrom PC·1 500) RAM3 S2 !from PC·! 500) RAM4 S3 (from PC-1 500) 5000 5800 SFFF 3 . Circuit description RAMI chip sefoct TC40Hl38 voo AOl2 vcc ADl3 8 YO 1 ADt 1 c Yi G2A Y2 G2B Y3 YO ACL DMEO Y4 Y5 GNO The RAM 1 is selected with a low state of Y7 which is issued when all of A, B, and C, are ltigl1 with high state of GI and low st:lle of decoder IC (TC40 Hl 38) gate inputs, G2A and G2ll. In othe• words, the RAMI Chip Select (CS) turns low state to select the RAMI in the following conditions: YO, ACL: low DMEO, ADI!. AD12, ADl3 : high The signal ACL, however, is the RAM contents protective signal an the time of power-on. Y6 To R At\11 chip select ·-· ,, ".. .·. ·'· ., ·>• h~AU LI:'. l':Zti A St:L l:Cl' c ·> ·.· ·=· ·:· -:· ... VT Vl! " " "" " ".. "" " " .. .. .. '· " " ' " " .. " " " " " " " " .. ..' " ".. " " .. .. "" "" "" " " " ''· ' ' " " "" " " . ' " " " " " . .," " .... " .;. ;;- H L L I. L L L L L L L H' Do not sale this PDF!!! H L ..,"'~'n " " " " " H H L " " " " "" VI .... " " " "" " " "" " "" "" " " " " " " ".. "" " " " " " " " " ' " " " "" " .. H L All and more about Sharp PC-1500 at http://www.PC-1500.info 4. CIRCUIT DIAGRAM TC.COllJJ.$ ) 11)16116 ~ n.o-+--- - " ~ ~ ... u •r ~ N > 0---. 0 ~ l ~ ' ~ Is .• ~ J.Q 111i15 11t1 e HM. 611 6 6' " rr o---+ < .... ::> ~ 0 ::> 0---. ,... "' <>-+-- z ~ v. 0N ~ .,-,<> 1; L1 ,.;:, .. ~ I 0 0- < ~ I 0 ~ ::: z0 :; ~. ll ~ • . !< 0 " ,.,,,,,, e ~r~T~r·I~ N T-T.. o;T;;T,, < ~< < < '"}_~< ~ ~513 llI ;: 1 IIJ 2 Do not sale this PDF !! ! 4 All and more about Sharp PC-1500 at http:f/www.PC-1500.info 5. PARTS & SIGNALS POSITION I 11 (; ... + - St.l:l'l91191'ill I -ii- t'J I S~-:1 .:1' 1 ~ (. 1t9l'iH llM6 11 6 l.Yt >.:s ,,. • ...""-' -- ..-.. ~ ~ ~ 3 All and more about Sharp PC-1500 at http://www. PC-1500.info 6. PARTS LIST & GUIDE PARTS COOE DESCRI P T I O N 1 GCA BA2637CCZZ 8011 orn cabinel 2 GCAB82638CCZZ ·r 01) cabinet 3 GCASP l 078CCZZ M OOulf~ case 4 GFTAUl243CCZZ M odvle case cover 5 PCUSU I I 76CCZZ C vshion 6 PH0G - 1092CCZZ Short rubbcf 7 TCAUH I I 79CCZZ Caution label 8 1 TLABZl642CC ZZ Modul~ lab()! . g SPAKC7002CCZZ Pack1n9 ('..ase 10 DUNT K6669CCZZ P WB unit VH ; HM6 11 6 // -I j LS; VHi TC40 Hl3 8FN .c RC- SZ l0 03CCNA CapacilO( RH - DZIOOBCCNI Doodc VRS- TP280 104J Resistor TiN SM3546CCZZ J I ns1 n;ct ion book - .'.!...;At< N I I l l I i I r I I 1 2 I I 0 D IA 0 A 0 IA D 9 4 Do not sale this PDF !! ! 0 IA c A B A A 0 -, N A 0 0 N ._ E 1 8 w E 8 8 8 A 0 i c I 8c I N D I 10 c c 0 3 6 IA c 0 J A A i . ,_ . N - I ~~~.~S :PftCE P.All< N F,;\': NO. c lA c A A A A () 4