Envelope-to: craig@sbc-85.com
Delivery-date: Mon, 06 Mar 2023 20:37:30 -0600
Date: Tue, 7 Mar 2023 02:37:18 +0000 (UTC)
From: Fred van Kempen <decwiz@yahoo.com>
To: "craig@sbc-85.com" <craig@sbc-85.com>
Message-ID: <2018861123.117437.1678156638313@mail.yahoo.com>
In-Reply-To: <0c0201d94c77$4a02b190$de0814b0$@sbc-85.com>
References: <1920779511.587308.1677386211891.ref@mail.yahoo.com> <1920779511.587308.1677386211891@mail.yahoo.com> <0c0201d94c77$4a02b190$de0814b0$@sbc-85.com>
Subject: Re: SBC-85 mailing address
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Got the package, thanks.
Finished stripping several industrial control boards (both 8085 and Z80 bas=
ed) thathad pretty much everything on sockets.=C2=A0 Nice addition to my pa=
rts bin, for next tonothing :)
I have decided I will build the backplane and cpu cards first, and go from =
there. Willhave to see where to get the PCI connectors, all other stuff I a=
lready have I think.=C2=A0=20

One thought that immediately crept up: we need a larger backplane (8 slots =
or so),and it HAS to have mounting holes on the corners and in the middle f=
or support. Imay have a go at that, based on the bp-4 design of course.=C2=
=A0 I would add a RESETswitch to it (for easy access), and, personally, I w=
ould move the actual RS-232"console" driver (MAX232) and connector to the b=
ackplane board, and only have aTTL pinheader for it on the CPU board.=C2=A0=
 That header would have the layout of thegenerally-available USB-to-RS232 b=
reakout boards, so for people operating JUSTthe CPU board, they can simply =
use one of those and they have console+power.
The backplane I would design with both the MAX232 *and* a USB chip, for sim=
ilarreasons.=C2=A0 USB3-based power profiles can draw up to 3A, USB2-based =
profiles candraw 500mA, although most hubs wont complain until you get to a=
bove 1A or so. Iwould probably use the FT232RNL, as I did in my other desig=
ns.=C2=A0=20

Anyway - lemme go and build one, first, eh? :)
--Fred
=C2=A0
 =20
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<html><head></head><body><div class=3D"yahoo-style-wrap" style=3D"font-fami=
ly:Helvetica Neue, Helvetica, Arial, sans-serif;font-size:13px;"><div>Got t=
he package, thanks.</div><div><br></div><div dir=3D"ltr" data-setdir=3D"fal=
se">Finished stripping several industrial control boards (both 8085 and Z80=
 based) that</div><div dir=3D"ltr" data-setdir=3D"false">had pretty much ev=
erything on sockets.&nbsp; Nice addition to my parts bin, for next to</div>=
<div dir=3D"ltr" data-setdir=3D"false">nothing :)</div><div dir=3D"ltr" dat=
a-setdir=3D"false"><br></div><div dir=3D"ltr" data-setdir=3D"false">I have =
decided I will build the backplane and cpu cards first, and go from there. =
Will</div><div dir=3D"ltr" data-setdir=3D"false">have to see where to get t=
he PCI connectors, all other stuff I already have I think.&nbsp; <br></div>=
<div dir=3D"ltr" data-setdir=3D"false"><br></div><div dir=3D"ltr" data-setd=
ir=3D"false">One thought that immediately crept up: we need a larger backpl=
ane (8 slots or so),</div><div dir=3D"ltr" data-setdir=3D"false">and it HAS=
 to have mounting holes on the corners and in the middle for support. I</di=
v><div dir=3D"ltr" data-setdir=3D"false">may have a go at that, based on th=
e bp-4 design of course.&nbsp; I would add a RESET</div><div dir=3D"ltr" da=
ta-setdir=3D"false">switch to it (for easy access), and, personally, I woul=
d move the actual RS-232</div><div dir=3D"ltr" data-setdir=3D"false">"conso=
le" driver (MAX232) and connector to the backplane board, and only have a</=
div><div dir=3D"ltr" data-setdir=3D"false">TTL pinheader for it on the CPU =
board.&nbsp; That header would have the layout of the</div><div dir=3D"ltr"=
 data-setdir=3D"false">generally-available USB-to-RS232 breakout boards, so=
 for people operating JUST</div><div dir=3D"ltr" data-setdir=3D"false">the =
CPU board, they can simply use one of those and they have console+power.</d=
iv><div dir=3D"ltr" data-setdir=3D"false"><br></div><div dir=3D"ltr" data-s=
etdir=3D"false">The backplane I would design with both the MAX232 *and* a U=
SB chip, for similar</div><div dir=3D"ltr" data-setdir=3D"false">reasons.&n=
bsp; USB3-based power profiles can draw up to 3A, USB2-based profiles can</=
div><div dir=3D"ltr" data-setdir=3D"false">draw 500mA, although most hubs w=
ont complain until you get to above 1A or so. I</div><div dir=3D"ltr" data-=
setdir=3D"false">would probably use the FT232RNL, as I did in my other desi=
gns.&nbsp; <br></div><div dir=3D"ltr" data-setdir=3D"false"><br></div><div =
dir=3D"ltr" data-setdir=3D"false">Anyway - lemme go and build one, first, e=
h? :)</div><div dir=3D"ltr" data-setdir=3D"false"><br></div><div dir=3D"ltr=
" data-setdir=3D"false">--Fred</div><div id=3D"ydp2377f756yiv1626481235"><d=
iv><div class=3D"ydp2377f756yiv1626481235WordSection1"><div><div><p class=
=3D"ydp2377f756yiv1626481235MsoNormal"><span style=3D"font-size:10.0pt;font=
-family:sans-serif;">&nbsp;</span></p></div></div></div></div></div><div id=
=3D"ydp2377f756yahoo_quoted_8489101999" class=3D"ydp2377f756yahoo_quoted"><=
div style=3D"font-family:'Helvetica Neue', Helvetica, Arial, sans-serif;fon=
t-size:13px;color:#26282a;">
            </div>
        </div></div></body></html>
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