{"id":930463,"date":"2024-02-21T16:40:12","date_gmt":"2024-02-21T15:40:12","guid":{"rendered":"https:\/\/blog.darkbyte.sk\/?p=930463"},"modified":"2026-04-16T14:13:41","modified_gmt":"2026-04-16T12:13:41","slug":"vhodne-typy-dram-pre-zx-spectrum","status":"publish","type":"post","link":"https:\/\/blog.darkbyte.sk\/?p=930463","title":{"rendered":"Vhodn\u00e9 typy DRAM pre ZX Spectrum"},"content":{"rendered":"<p align=\"justify\">Opakovane sa mi stalo, \u017ee mi prist\u00e1lo na stole nejak\u00e9 ZX Spectrum, ktor\u00e9 opravoval niekto in\u00fd a napriek \u00fasiliu sa ho nepodarilo rozbeha\u0165 a po\u010d\u00edta\u010d st\u00e1le vykazoval chyby pam\u00e4te, napriek v\u00fdmene \u010dipov za nov\u00e9. Probl\u00e9mom bol typ pam\u00e4t\u00ed, ktor\u00fd tam moji predchodcovia osadili. Dnes si teda vysvetl\u00edme, ak\u00e9 pam\u00e4te je mo\u017en\u00e9 v ZXS pou\u017ei\u0165.<\/p>\n<p><!--more--><\/p>\n<p align=\"justify\">V ZX Spectre sa pou\u017e\u00edvalo nieko\u013eko druhov pam\u00e4t\u00ed od viacer\u00fdch v\u00fdrobcov. V ZXS 128k a \u0161edej +2 sa pou\u017e\u00edvali pam\u00e4te 4164, v +2A\/3 sa pou\u017e\u00edvali pam\u00e4te 4464. No a napokon v ZXS 48k \/ Plus sa pou\u017e\u00edvali v oblasti video RAM typ 4116, v oblasti hlavnej RAM typ 4532, \u010do je vlastne 4164 s amputovanou nespo\u013eahlivou polovicou, ktor\u00e9 Sinclair nakupoval, aby ZXS dostal na cenu, za ak\u00fa sa pred\u00e1valo. Zast\u00e1vam n\u00e1zor, \u017ee pri oprav\u00e1ch ZXS 48K sa u\u017e netreba za\u0165a\u017eova\u0165 zh\u00e1\u0148an\u00edm 4116 a 4532, ale treba pou\u017ei\u0165 bez probl\u00e9mu dostupn\u00e9 4164 s t\u00fdm, \u017ee pri os\u00e1dzan\u00ed do VRAM treba upravi\u0165 nap\u00e1janie, ke\u010f\u017ee na rozdiel od 4116 si u\u017e vysta\u010dia len s piatimi voltami.<\/p>\n<p align=\"justify\">Len\u017ee nie je 4164 ako 4164. Pod t\u00fdmto typov\u00fdm \u010d\u00edslom sa skr\u00fdva dynamick\u00e1 NMOS pam\u00e4\u0165, organizovan\u00e1 ako 65535-word x 1-bit, teda pre 64kB potrebujeme 8 tak\u00fdchto \u010dipov. Zrada je v tom, \u017ee s\u00fa dva typy t\u00fdchto pam\u00e4t\u00ed a odli\u0161uj\u00fa sa v tom, ako s\u00fa vn\u00fatorne organizovan\u00e9. Star\u0161\u00ed typ m\u00e1 maticu 128 riadkov x 512 st\u013apcov. Nov\u0161\u00ed typ m\u00e1 maticu s 256 riadkami x 256 st\u013apcami. \u013dudovo povedan\u00e9 l\u00ed\u0161ia sa refresh cyklom &#8211; je bu\u010f 7-bitov\u00fd, alebo 8-bitov\u00fd. Star\u0161\u00ed typ m\u00e1 teda <em>128 cycle \/ 2ms<\/em> refresh, nov\u0161\u00ed <em>256 cycle \/ 4ms<\/em> refresh. Pre ZXS je vhodn\u00fd v\u00fdhradne len prv\u00fd z nich a problematick\u00e9 je, \u017ee sa vyr\u00e1bali s\u00fabe\u017ene a preto treba starostlivo \u0161tudova\u0165 dokument\u00e1ciu. Bol som presved\u010den\u00fd o tom, \u017ee za tie roky je toto u\u017e notoricky zn\u00e1my fakt, ale ukazuje sa \u017ee nie je. \u00daplne chronicky \u010dasto sa mi dost\u00e1vaj\u00fa do r\u00fak ZXS s osaden\u00fdmi HYB4164 alebo TMS4164, ktor\u00e9 s\u00fa nevhodn\u00e9.<\/p>\n<p align=\"justify\">T\u00fdm, \u017ee ZXS opravujem pomerne \u010dasto a pam\u00e4t\u00ed nikdy nem\u00e1m v z\u00e1sobe dos\u0165, v\u017edy nejak\u00e9 priebe\u017ene objedn\u00e1vam a tak som si za tie roky spravil slu\u0161n\u00fd preh\u013ead, ktor\u00e9 sa daj\u00fa pou\u017ei\u0165 a ktor\u00e9 nie. Aj z t\u00fdch so 7-bit refreshom sa orientujem len na tie s pr\u00edstupovou dobou 120 a 150 ns, lebo s r\u00fdchlej\u0161\u00edmi aj pomal\u0161\u00edmi som mal probl\u00e9my. Napr\u00edklad NEC \u00b5PD4164C-10 som nerozbehal ani napriek dodato\u010dnej snahe zladi\u0165 RAS a CAS pod\u013ea dokument\u00e1cie.<\/p>\n<p align=\"justify\">Aby ste to u\u017e nemuseli h\u013eada\u0165, spravil som pre v\u00e1s tieto dve tabule\u010dky s vhodn\u00fdmi a nevhodn\u00fdmi typmi. Nie je to zoraden\u00e9 pod\u013ea abecedy, ale pod\u013ea toho, ako mi postupne prib\u00fadali do zoznamu. Samozrejme, \u017ee tam nie s\u00fa v\u0161etky pou\u017eite\u013en\u00e9 typy ale len tie, ktor\u00e9 som mal mo\u017enos\u0165 otestova\u0165.<\/p>\n<p align=\"justify\"><strong>Vhodn\u00e9 typy:<\/strong><\/p>\n<table>\n<tr>\n<th>V\u00fdrobca<\/th>\n<th>Typ<\/th>\n<th>Suffix<\/th>\n<\/tr>\n<tr>\n<td>Mostek<\/td>\n<td>MK4564(J)(N)<\/td>\n<td>-12, -15<\/td>\n<\/tr>\n<tr>\n<td>Mostek<\/td>\n<td>MK4164(J)(N)<\/td>\n<td>-12<\/td>\n<\/tr>\n<tr>\n<td>Toshiba<\/td>\n<td>TMMC4164(C)(P)(AP)<\/td>\n<td>-2, -3, -12, -15<\/td>\n<\/tr>\n<tr>\n<td>Samsung<\/td>\n<td>KM4164<\/td>\n<td>-12, -15<\/td>\n<\/tr>\n<tr>\n<td>Fujitsu<\/td>\n<td>MB8264(A)<\/td>\n<td>-12, -15<\/td>\n<\/tr>\n<tr>\n<td>Fujitsu<\/td>\n<td>MB8265(A)<\/td>\n<td>-12, -15<\/td>\n<\/tr>\n<tr>\n<td>Hitachi<\/td>\n<td>HM4864(A)(P)(AP)<\/td>\n<td>-2, -12, -15<\/td>\n<\/tr>\n<tr>\n<td>OKI<\/td>\n<td>MSM3764(A)<\/td>\n<td>-12, -15<\/td>\n<\/tr>\n<tr>\n<td>Matsushita<\/td>\n<td>MN4164P<\/td>\n<td>-12, -15<\/td>\n<\/tr>\n<tr>\n<td>NEC<\/td>\n<td>\u00b5PD4164(C)(D)<\/td>\n<td>-3, -12, -15<\/td>\n<\/tr>\n<tr>\n<td>Motorola<\/td>\n<td>MCM6664(AL)(AP)<\/td>\n<td>-12, -15<\/td>\n<\/tr>\n<tr>\n<td>Motorola<\/td>\n<td>MCM6665AL<\/td>\n<td>-15<\/td>\n<\/tr>\n<tr>\n<td>AMD<\/td>\n<td>AM9064<\/td>\n<td>-12, -15<\/td>\n<\/tr>\n<tr>\n<td>TESLA<\/td>\n<td>MHB4164<\/td>\n<td><\/td>\n<\/tr>\n<tr>\n<td>IME, Bulharsko<\/td>\n<td>CM8164<\/td>\n<td><\/td>\n<\/tr>\n<tr>\n<td>?, ZSSR<\/td>\n<td>KP565PY5<\/td>\n<td><\/td>\n<\/tr>\n<\/table>\n<p align=\"justify\"><strong>Nevhodn\u00e9 typy:<\/strong><\/p>\n<table>\n<tr>\n<th>V\u00fdrobca<\/th>\n<th>Typ<\/th>\n<th>Suffix<\/th>\n<\/tr>\n<tr>\n<td>Micron<\/td>\n<td>MT4264<\/td>\n<td>v\u0161etky<\/td>\n<\/tr>\n<tr>\n<td>National Semiconductor<\/td>\n<td>NMC4164<\/td>\n<td>v\u0161etky<\/td>\n<\/tr>\n<tr>\n<td>Siemens<\/td>\n<td>HYB4164<\/td>\n<td>v\u0161etky<\/td>\n<\/tr>\n<tr>\n<td>Fairchild<\/td>\n<td>F4164<\/td>\n<td>v\u0161etky<\/td>\n<\/tr>\n<tr>\n<td>Texas Instruments<\/td>\n<td>TMS4164<\/td>\n<td>v\u0161etky<\/td>\n<\/tr>\n<\/table>\n<p align=\"justify\">Nem\u00e1te za \u010do \ud83d\ude1b<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Opakovane sa mi stalo, \u017ee mi prist\u00e1lo na stole nejak\u00e9 ZX Spectrum, ktor\u00e9 opravoval niekto in\u00fd a napriek \u00fasiliu sa ho nepodarilo rozbeha\u0165 a po\u010d\u00edta\u010d st\u00e1le vykazoval chyby pam\u00e4te, napriek v\u00fdmene \u010dipov za nov\u00e9. Probl\u00e9mom bol typ pam\u00e4t\u00ed, ktor\u00fd tam moji predchodcovia osadili. Dnes si teda vysvetl\u00edme, ak\u00e9 pam\u00e4te je&#8230;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[22],"tags":[],"class_list":["post-930463","post","type-post","status-publish","format-standard","hentry","category-zx-spectrum"],"_links":{"self":[{"href":"https:\/\/blog.darkbyte.sk\/index.php?rest_route=\/wp\/v2\/posts\/930463","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blog.darkbyte.sk\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blog.darkbyte.sk\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blog.darkbyte.sk\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/blog.darkbyte.sk\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=930463"}],"version-history":[{"count":13,"href":"https:\/\/blog.darkbyte.sk\/index.php?rest_route=\/wp\/v2\/posts\/930463\/revisions"}],"predecessor-version":[{"id":930472,"href":"https:\/\/blog.darkbyte.sk\/index.php?rest_route=\/wp\/v2\/posts\/930463\/revisions\/930472"}],"wp:attachment":[{"href":"https:\/\/blog.darkbyte.sk\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=930463"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blog.darkbyte.sk\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=930463"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blog.darkbyte.sk\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=930463"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}