Marten Whopper Memos

Date: March 1~, 1983 · To: I.Jayne Rosing Ken Okin ,. Jon Fitcn Ron HOchsprung l.Jendell HenrY. Riek Meyers · Ricn"'Page Bruce Daniels vn1ke Urquhart Art BenjaPtin Paul Baker Am Nunziata IJOlfgang Dirks 200 Fr1:>Pt: Gary Marten • Sutlj: Vl.. 75 ·• • I Here is wnat is nopefull~f close to t~ final def ini t1on of 1. 75. As you recall, 1. 75 is the . currtmt Lisa wi tn a new logic cage assel'1ll y and a neY disk drive asserilly. • . . (} ~ ~"'t- syster1 cmr1CJ.II'a't1Cl'1 o 10 MHZ 68010 prt:>eessor o 720 x· 364 videO display 10 MB ou1lt-1n tiara OlSk . . . Built in floppy disk ·. o o a o o o 0 MMU witn 512 byte paoes ~ & °'ho~t Hth 'i1~/.e4 ·~ "4' h~zz-~ 6Z'Z 7-j~eYr ? '-' fA.e-·<t.. ""v-e tA.-5-e.o/ ex.fev-~,·vefy. . , L,,, A .1&p~/ff1~'~b'~/'--~ ~ ) ....,. (3) wh1'cL 128/256 Kbytes FQ1 ~ jiyllf-?~J! 0\:..-e / · little rore difficult, but dOatJle. To ca•pensate for tne 2 regaeyte 11M:itation ~f the 512 byte page. scnerra, anotner 2 Plegat)yte aaaress space has Deen added, for a tot.al of 4 regat>ytes of aCJCJress space. The stanaara PePDry cycle tire will De soons, 1ncluaing tif'ltl tnrough the MMU. Po?:lty Errors It "3s earlier tnougnt thiat Motorola h~ corrected the proDleM tnat 1ntt:tb1ts us froPt generating cus errors aue to rwerory parity errors. This is not the case nowever. Therefore the current, SCneMe of generating an NMI on a parity error will nave to rera1n . 01·1ves The design of 1.75 rias·reuea on contl'Olling tne floppy d1Sk i-1itn tne 68000.. This dOes not appt'8r to be a Protllf!t'f. · Th!3 hard dlsk w111 prObabJly also t:>e controlled directly by tne 68000, tn1s elMi.nates tne prOblet'lS of r"1ss1ng 1nter1eves dUe to excess! ve recopying of aata1 at slow rates. · · Review There will be a review of 1.75 on Tue&$y, Maren 22~ at 3:30 in The Big Apple. ? ~h>vi~. 1vt ~ t/ ,~ c/,~? ~~/~ Dual serial por1:s Y~ _,,,,, tft.) · Parallel Port (j.f n~)& of C-'llW'~e.' ,;.,.. ex~ "' Mt!!- -&f1oi..t w'(/'l,i 'hMh F' 10,,.,..., 896 Kbytes RAM The tllJ ancJ MePmy Addles,s Space The 512 byte page size will rel'191n.- This P&<es the use of 256K RAMS a 01~~ ,/J Those interestea aire welcorwa. ·1.75 .Me~mory ConfiguratiQns Uith 2-2 t1eqabyte ftapped address sp~s with 512 byte resolution :3/ 4 Megabyte 1'1ePH::>ry t1oard First 2 negaDyte addre~S ·o on Board RAM 3141. 3/4 MB space 2" 0 Second 2 !Megabyte Slot 4 ~ 1 ·rs lft ... address space Slot 5 - 1 MB 2ft ., 1. 1/2 Megabyte P18P't0ry board . I 0 On. Board RAM First 2 Megabyte address space l 112ft. l 1/2 MB 2" 0 second 2 r1egat1yte aaaress space Slot.4 - l·MB 1ft 21'1 Slot s - 1 re 3 Megabyte PM!P10ry boeJrd 0 First 2 ME~yte On Board RAM address space 2ft 0 3 rve . second 2 Mtag&Dyte lJt ~SS ~;pace 31 Slots 4&5 are the old · mtnory card locations Slot 4a5 - 1 MB (Slot stlected by st.It.us bitt J/14183 en 1.75· ~emery Allocation " .. •5"ota1 • Address ~ V.irt.u4l Addnss Spece Seoftent o.. 32 .. 64 .. 96 Se~ne…