[Music]
welcome back from the break everyone
hope you had a lovely step away from
your computer or a social time in any of
the chat channels or um whatever it is
that you like to do in your online
conference breaks
next up we have randall crook
telling us how open source and hardware
has changed retro computing
so randall is a unix system
administrator with a checkered
background in electronics integration
and nick's admin
recently has become inter more
interested in retro computing gathering
an eclectic collection of old computers
and modern clones of 8-bit systems and
now he has been playing some interesting
open projects that have impacted his
hobby in retro computing
so randall will be answering questions
at the end
so please
put your questions in the questions tab
in venulis and i will pass them on to
randall at the end of the talk um i
think this is going to be a fun one so
enjoy everyone over to you randall
g'day um
i'd like to acknowledge that i'm meeting
with you today from the lands of the
none of all people i also acknowledge
the traditional custodians of various
lands on which you all participating
today and pay respect to the elders past
present and emerging and extend that
respect to other aboriginals joining us
today
today i want to talk to you about my
hobby
but a bit about me first i'm as
betsy said i'm a systems
just uh just to let you know uh randall
we've had a sound card drop out on you
your audio has dropped out so um
might just want to uh go to cam mic
settings and um
swap sound card out and swap it back
again and just see
there we go i think you're back
hello we can hear you i can hear you
we're good thanks
okay
so
my background in computing in general
starts back um when i was in high school
actually the first ever computer i
touched or used was an apple 2e at my
high school
the first ever computer i actually owned
was a second hand sinclair zx81 and if
anybody's ever had a play with this is
the zx81 you'll know it's not a
particularly
useful computer it is useful for
learning about
basic and and how
home computers work
from there i went to a commodore 64 and
i'm pretty sure
a large number of people who are
watching this at the present moment have
used a commodore 64.
mine only had a tape unit and the
favorite game on it was the
shuttle simulator and boy did it take
time to load off the tape
up until that point i wasn't overly
impressed with
with um computing
because at the same time as i had them i
was working for a company that actually
had a couple of ncr towers
which ran unix system five release three
they were in 68 000 based machines with
two megabytes of ram and 20 megabyte
hard drives
they impressed me having multiple users
running
different work
different programs as they were called
back then that's what i thought was
computing
then about 1986 i bought my first amiga
and it was the original omega then
written later renamed it to the amiga
1000 and i loved it i was sold that felt
like computing it had preemptive
multitasking it had a
a
beautiful
gui
gui interface well before its time
and i loved that
computer i even upgraded to the amiga
500
a few years later and
i'm kicking myself now because i didn't
keep it i actually gave it away to a
friend
anyway
in the early 90s i moved on
to working with pcs and the pc
domination sort of flooded in and all of
the old computing
systems that i had either vanished were
given away or sold and i was stuck with
pcs
fast forward to 2019
and
i was sitting there in a fit of a
nostalgia on ebay looking for a hp
5036a which is a microprocessor lab it's
a processor trainer that i was using
when i was doing my associate diploma
back in the late 80s early 90s
and couldn't find one
um the ones i'd seen that have been sold
recently were going for ridiculous pro
amounts of money so
so i was very disappointed then i came
across a printed circuit board being
sold by a gentleman not far from
canberra
he
discovered talking electronics a
magazine which had been released
that had had a run through the early 80s
and a couple of gentlemen here in
australia designed a single board z80
computer for the magazine
the gentleman i stumbled across on ebay
in 2019 had actually updated the printed
circuit board and had a bunch made
primarily for himself but he was selling
the
the others on ebay i bought one
and i built it and it was the beginning
of my trip back down memory lane
i then bought a couple of um old apples
uh an apple tusea and a mac classic off
a friend of mine tim thanks very much
for them i then proceeded to restore
them
and then i got immersed into the retro
computing youtube
channels there's quite a few out there
if you haven't had a look i'm sure most
of you know
the one i'm about to mention which is
the retro man cave
neil back in october 2019 did a video
about the newest amiga 500.
on there he built an amiga 500 using a
replica board that had been designed by
rob taylor
and was
being sold for people to go out and
build their own amiga 500s
and of course i had to buy the board i'm
an amiga fan i bought one i scraped it
all together
and
first powered it up in may 2020 and it
went straight to the kickstart
screen as you can see there because it
wasn't perfect i still had no sound but
it didn't take me long to figure out
what was wrong with the sound and get it
working
the omega 500 plus plus will play a part
in this talk
and this is it this is the finished
product
it took me about three weeks to build
after i'd got all the components
together
it was thrown together with bits of old
computers which were no longer working
a german keyboard which i managed to get
off ebay
and
it works beautifully
and this is the basis or the base
platform that i use to discover some
very interesting open source projects
let's
take a bit of a diversion here and talk
about the pine invasion of the retro
computing enviro
community
one of the biggest issues with playing
with retro computing
is the vanishingly scarce
peripherals required to get some of
these computers to work
and the pie
has been used for the basis of a number
of very useful
peripheral
recreations or emulations like the pi
1541 which emulates
uh commodore 1541 floppy drive
you've also got the rascazi which
emulates a whole bunch of different
types of scuzzy devices
for any of the systems that can actually
support scuzzy
and there is also
a commodore tape emulator
used using a raspberry pi
but the two i'm talking about today are
the rgb h to hdmi
and the pi storm
these two uh
projects
a focused
uh that may be used in in fact can be
used on a a number of different
uh retro platforms
but in my case i'm looking at the the
derivations require derivations
specifically for the amiga
the rgb hdmi
its primary focus when it was originally
started was to
enable people to
to view the output of older computers
on modern
monitors
the uh
retro monitors of the time are cot-based
ones and they're becoming harder and
harder to source they're becoming harder
to repair and
when you do find them on ebay and on the
different marketplaces they usually
attract a very large sum of money
there are other
there are other projects out there at
the present moment which will do
upscaling and video conversion for these
old older products or older computers
but they
usually fairly expensive things like the
ossc which is another open source one
um at the present moment they go for
about 150
australian to buy very good
but expensive
and on top of that many of the old
computers actually have
either proprietary or very esoteric
video standards uh
i'm
looking at the video standard of hp 9000
at the present moment which i don't have
anything which can convert it
just yet
but i will find something
and the pie is
the reason they're using the pie is
because number one the pie zero in
particular is cheap
20 odd bucks here in australia
it's a known platform that's been used
extensively not just in retro computing
but across the entire technology
field
it's got an open development environment
it's
cheap to sit down and
develop
interfaces that use the raspberry pi
to handle things like video or scuzzy
or
older networking protocols
this is the one
for the amiga 500
as you can see it's not particularly
large it doesn't appear to be very
complex and it isn't it's essentially
just some 74 series logic chips and a
level conversion
um from the 5 volts ttl on the omega 500
to the 3.3 volt
levels required by the raspberry pi
it's designed to be small to fit
underneath the graphics chip of the
amiga 500
it's the graphics chip's called denise
uh they 500 the
the actual um
board sits underneath the the denise and
this plugs into that then the raspberry
pi plugs into that and you may be able
to see the black ribbon cable
that's actually a hdmi cable that runs
from the raspberry pi
to an external hdmi port in a in a 3d
printed clip-on case so it's to not to
damage the
the actual case
and this is what
the output looks like
this was actually captured by a very
cheap
hdmi capture card
and it's the amiga is running in its
high resolution interlaced mode and if
anybody
remembers running the interlaced modes
on the old crts it was terribly
annoying the amount of flicker the
interlace introduced well it's
it's good to hear that they've actually
removed the flicker
using the algebra hdmi no flicker at
high resolution
looks
awesome the next
the next project i'm going to talk about
which is another open project is the pie
storm
at its heart it is a drop-in replacement
for the motorola 68000 cpu
and then still available and they're not
overly expensive but what this allows
you to do using the the emp 240 cpld and
a bunch of 74 series latches and
transceivers is to actually emulate not
just the 68 000
but
the later
revisions and the later versions of the
68k series like the 030 and the o4o
it uses a raspberry pi 3 a plus
primarily to get the performance
required for emulating a 68 000 cpu but
also it's a very low profile which means
it'll fit
just inside an omega 500 case
this is what the pie storm looks like as
you can see it's got the cpld and a
bunch of latches 7 4 series latches and
some interfacing
once again interfacing
circuitry with a level
um shifter
once again because of the 5 volt 3.3
required by the amiga
the raspberry pi and it is
once it's together just fits underneath
the keyboard of the a500
it as i said earlier it can emulate
anywhere up to a 68040 running at it
it runs at about seven or eight
megahertz it's hard to tell because
it's a user land
emulation program running on the pi
but it
can give you quite a good performance as
seen on here it can emulate uh or it can
it can
get performance better that just better
than the the the four thousand running
you know for 20 25 megahertz
this is in its current form
they are working on an emulation um
an emulation program at the present
moment
which should increase the performance
greatly
but the pi storm is not
just an accelerator
it does a hell of a lot more
when you think that there is a raspberry
pi sitting on top of the the cpld and
controlling it
you can do a lot more things
right from the raspberry pi itself and
you can
set up virtual rom images and be able to
change
change them in the configuration from
kickstart 1.3 to the very latest
kickstart 321
plus diagrams etc
you can map
up to 128 megabytes of ram
into the fast dram area of the amiga
you can map virtual scuzzy disks
which are images
that can be used within the amiga
emulator
two virtual scuzzy drives within the
amiga itself
there is
um
a directory uh pi resident or file
system resonant directory mapping
facility so you can actually map a
directory from the raspberry pi's file
system to a virtual scuzzy
or a virtual disk
within the amiga os
you can also fire up a shell from the pi
within the amiga os shell
and there is another part which i
haven't haven't been able to get working
as yet which is the retargetable
graphics which allows for
high resolution graphics on the amiga
via the pi g gfx
library through the hdmi output of the
pi
and one of the most useful
is you can now use the pi storm
to gateway into the internet via the
pi's wi-fi
so if you're running a tcp stack on your
amiga you can actually connect to the
internet
and of course they've thrown in the
real-time clock as well
now it's time for a short video
demonstration i'll
talk over this and and you'll see some
of the pluses and minuses
the first part is the power on which is
a minus can take anywhere up to a minute
the reason for this is the
the pi storm holds the reset line on the
amiga low
until the pi is fully booted and the
emulator software is actually running on
it
then it releases it
and the system will then boot
and as you can see
this uh this is my a500 plus plus it
boots up once it gets to that point it
boots up pretty quickly
and to show an example let's just say
how quickly it can boot i'll do a reset
here and
from the three finger con
salute
back to useful is about 25 seconds which
is not bad for the for the old omega
500.
the next thing i'm demonstrating here is
the actual
use of an amiga
or the pi storm's networking
capabilities
aweb is a very old web browser
made in the in the 90s for the amiga and
if you get a chance have a look at
frogfind.com
it's a
search engine specifically designed for
retro
browsers
and it uses the
mozilla reader
library to strip everything out that
a um
retro browser like this one would not
like
and as you can see you can browse um
github if you want using it the amiga
500 i mean it's still a bit slow
even with the the acceleration but
hopefully that'll be resolved with the
new m in emulation engine
and of course no demonstration um
no demonstration of the past normal
would be without the cis info
this will give you a quick rundown as
you can see it thinks it's a 68 040 with
a
60 uh six triple eight two mass
co-processor it's got the 128 megabytes
of ram plus two megabytes of chip ram
it's got all the
um
different dries connected both physical
and the pi scuzzy virtual ones
and we can do a speed
check
and it comes up with um
just over 20 20 000 dry stones which is
pretty impressive for an amiga 500
and the performance of
the actual virtual drives is still
pretty impressive too 20 25 mega
bytes per second
and lastly
or not lastly but i will now
show you a demonstration of its sound
it still works soundtrack it still works
and
we'll play an old um
mod from a a game called crystal hammer
and you'll be able to
see that the pie storm still supports
the sound and everything
lastly i'll show you the um
the virtual
disk that maps to a directory within the
raspberry pi which makes it very very
useful you can actually use
ssh or even samba
to
share a directory within the pie itself
on the pie store
and everything in that directory will be
accessible from within amiga os
it's a bit slow but they are trying to
fix the performance on
on the
shared directories
as you can see that's the
you do it essentially you mount the
virtual drive which is called pi zero
um it'll then show up on the the
workbench you can then
open that up and have a look at it
in on the raspberry pi it's
itself that's an ssh connection into the
raspberry pi as the um amiga is running
there's a a directory
which is mapped to the pi disk on the
workbench
we can create a file here
just an ordinary text file this
particular point
just anything in it doesn't particularly
matter
and when you refresh
on the amiga 500 refresh the directory
in this case i'm just going to close the
window and and reopen it you'll find
that the file is now there available
within mega os
that's all the systems running so very
very useful for
transferring data on and off
the amiga
and you don't have to
swap disks or pull sd cards or whatever
and that of course is all running over
the
the net the wi-fi of the raspberry pi
that's it for for the demo
and we'll move back on
with the talk and i'll do a
quick wrap-up you've got to understand
the pi storm project is still in beta um
there are still lots of lots of hardware
and software compatibility issues that
that you'll come across
[Music]
the power on boot time is is
one of the most annoying things but
it can be fixed by going in and tuning
the the version of
linux that you're running on your pi
the one i got there cost me a total of
seventy dollars when i originally bought
it that's the raspberry pi plus the pie
storm the present moment with the chip
shortage they're running at about a
hundred dollars
full for a pie storm and the the actual
raspberry pi so it is well worth looking
at if you've got a 500 and you want to
expand it
well worth looking at that particular
project
the next thing i want to talk about
is a very interesting
project open project
which is impacting the home homebrew or
retro brew commun uh computer
um community it's called ron wbw
but
you've got to understand that the the
retro and homebrew community has been
around for a long time
um its roots go back to the computer
enthusiast clubs of the 60s and 70s in
fact apple's very first product was
aimed at the the members of those clubs
which was the apple one
the desire to tinker
with your stuff
um has not died
it's instead it's actually getting
stronger all you have to do is look at
the number of maker clubs out there
um
but at the same time the technology uh
complexity is is fast surpassing the
hobbyist's ability
and that's where the retro in homebrew
community comes from
because it's using the old computer
technology
and in this particular case the rom wdw
is aimed at the z80 based processor it's
an 8-bit processor which is still being
made today you can still buy brand new
z80s in the dip 40 package
there is an immense amount of data and
information available for the z80 it's
been around for so long it's accumulated
so many
fans and users both commercial and
and open
that
it's very easy
as a starting point for your own
computer if you feel like building one
and there is a
still a large variety of of development
platforms out there you can
do what most do which is the assembler
which is
not particularly good
but it is a well-known assembling uh it
is a well-known instruction set and very
very straightforward to use
and there is an immense amount of of
software which is out there still
in fact
you can build a z80 based computer
very simply
even into a very small
computer
that's an scs-130 which i'll talk about
later on
and there's i mean there's plenty of
cpus you can certainly choose as the
basis of a of a homebrew computer and
the 6865
the 68 000 6800 the 6502 the 1802
they're all still relatively easy to
pick up and they're all relatively easy
to program for and there is a lot of
things a lot of pla
programming languages you can actually
use on them
now apart from what i've mentioned the
other attractiveness of the z80 is it's
is it some place in computing history
there was an awful lot of z80 based
computers released
at the beginning of the 80s and
right through until the 90s and the
k-pro luggables for example the osborne
one
and right now there is in fact an
operating system you can buy so sorry
you can download
for a zld based computer and it's
available free of charge and it is now
open source and that's cpm
the
cpm um which was created in 1974 by
digital research it's a predecessor of
dos
and has changed hands a few times
but when caldera owned it in 1970 in the
1990s they released
cpm
2.2 binaries and source code um under an
open source license so it is now open
source
and it is an advanced operating system
for
for for retro computers
and a lot of retro computers um
are now currently using it and it's not
just a z80 there's 8085 8086 and 68 000
versions of cpm available
now i want to talk about wayne worthen
that's a very smart bloke i managed to
interview him for about an hour for this
talk
he
has a passion at the present moment for
doing
the work he is on the wrong wbw
when he started looking at
the home brew or the retro brew
community it found a lot of the
computers that were being made
essentially
it was the developers or the the
designers who wrote their own rom
monitor and they were philly
they were while they were good they were
not particularly versatile
wayne saw this and he wanted to
essentially write a standard
for
z80 based
retro homebrews or retro brew computers
and
his primary motivation was to create a
professional level cpm system out of a
homebrew computer
now
his first
go at this was um
specifically for the in the nhvm
homebrew computer by andrew
lynch
um
and he put that out on to the on to the
homebrew forums and people jumped at it
um
and he's the first guy who jumped on and
and started working with wayne was uh
sergey kiselev
for his zeta single board computer
and
after he
integrated the zeta with the help with
sergey even more people
started to talk to him about getting
from wbw running on their home computers
so what is the rom wbw it's a it's
essentially a bios it's mostly written
in
z80 assembler and it gives
low-level initialization uh
for
for the system when it first powers on
it supports a bunch of different system
peripherals and expansion it has boot
loaders for multiple operating systems
including physics which is alan cox's
little
micro
um unix-like operating system
well worth having a look at
it also has the the bias routines
required for cpm
floppy disk controllers ide controllers
spi and i squared c device interfacing
functionality as well
so you can actually plug in spi and i
squared c
devices and easily get them integrated
into on wbw
plus it's got built-in
a 300k cpm ram disk
and rom resident cpm bootable disk very
basic functionality on the rom wb of the
the rom resident cpm bootable disk but
it works and it works beautifully and
takes us back to the days of days of
rebootable systems on like the old
classic macs etc
the systems that currently support as
you can see there's quite a few
i've got a few of these including the
zeta 2 and
the rc 2014
as well as the 126 the 130 and the 133
the 133 is the one i showed you here
it's a cpm machine that fits in your
pocket all you have to do is plug it
into your usb port
it does have
an sd card slot in it as well
but it also has
vga and ps2 support
using the parallax propeller micro
controller it has the support for sound
cards
and there are a number of
video display unit
projects currently working with wayne to
get them included
now i don't know how much time i've got
left unfortunately i haven't got my
timer here um
but i was going to do a live demo of one
system i'll start and if betsy wants to
jump in when i
run out of time
you might be able to see some of the
system some of the system stuff anyway
let's have a look
now this is a
this is the sc126
um
it's i do have a photo and i'll show
show you once i've done but at the
present moment it's running uh the very
latest version of the
development
um
branch of the rom wbw when you first
power it on as you see it comes up with
a bunch of um
what your class is post well it is post
information and then it gives you a
summary of what hardware it knows
from here there's a number of things you
can do
the boot
the boot um unfortunately it doesn't
list all the the options in the help
but starting with say the
monitor program this is a basic
monitor
or your rom based monitor and it gives
you
your
your monitor functionality if you want
to do some debugging
you can actually get this to software
reset and leave the ram alone so if you
want to if you've got an issue
you can actually reboot
fire up the monitor and actually see
what's in ram
i'm going to do a quick dump
some ram
here
ram or wrong
and as you can see it comes up with
that's part of the rom
then we can move on to
something which i think will give give
everyone a bit of a
a giggle
this has rom resident basic
and it is in fact microsoft's basic
which was released to public domain
quite a few years ago and it's been used
quite a bit in the retrobrew community
and yes it is standard
microsoft basic
with the standard
standard syntax
we do a list
and a run
off you go
it also has another more advanced
version of
open source basic called tasty basic i
won't demonstrate it
it does have a few extra functions built
into it to enable you to do things like
reading
registers and stuff like that from
within a basic program it's very useful
it also has fourth now i know nothing
about fourth at all
so i'm just going to show you the banner
and i'm going to reboot so if you know
fourth
this is quite a nice little machine to
play with with fourth
another thing at arm has
built in as a game there's a game in
here
if here p
i have no idea what game it is i've
never played it i just know it's there
so if you want to play a game on a z80
using a serial port this is the machine
for you
but we'll get to the the killer app
which is
cpm
now i've got an sd card on this
which has got a number of spins of cpm
on it i've also got a
there's also the built-in cpm which is
2.2 and i'll fire that up
you hit c it'll boot up
the rom resident version of cpm
and as you can tell it hasn't got an
awful lot of things in it but what it
does have in it
is the tools
required if you want to start building
up your own disk images
it also has a tool for flashing
the
rom so if you want to put a new rom on
your system you can actually
put it into it
to a partition on the sd card which is
formatted as fat you can copy it across
into the ram disk well you can't because
it's too small but you can actually copy
it onto an sd
card partition and then flash the rom
from within cpm
very useful
if we go on and have a look at what i've
got installed on
the sd card
as you can see it's a 16 gigabyte sd
card disk number six
if you specify which disk you want or
which device you want to boot from and
then a partition number i'll use
partition 4
[Music]
and this boots up a
very much
customized version
of
cpm that it's that has
added a whole bunch of more useful two
utilities but also a much
friendly user interface if we change to
one of the other
drives here you do it
it now does paging
for the directory
uh directory listing which is very
useful
um
and
this is the the version of cpm i use uh
mostly when i'm actually working on the
the rom wbw machines i have
there is a fat utility
which i believe is on a
um
no it's not on a
here it is here so i can do it i on that
16 gigabyte hard
16 gigabyte sd card
only the first
i think it's 128 megabytes is actually
used by cpm
it creates a bunch of
[Music]
cpm specific
partitions at the beginning of the disk
the rest of the disk can then be
formatted as fat
and actually used within a
a modern computer for transferring files
across in this particular case you'll
see that i've actually got
on here a copy of the rom
for this particular machine
and so what i can actually do is copy
that
onto one of those cpm partitions so if
we do a fat
copy
for 126
dot
rom
to f drive
[Music]
i've got a four there that shouldn't be
there
i've got the 4
colon
126
to f
it will now copy that file drive not
ready
as with all
live demos
there's got to be something that goes
wrong
anyway
once it's copied across
onto
the
directory
onto one of the partitions for cpm
you can then actually flash that rom
onto the
flash rom it's actually a flash rom that
sits here and
that's how you upgrade the rom
how much time have i got left i think i
must be getting pretty close
you've got
three minutes and 47 seconds
i would love to i would love to show you
the sound card working but unfortunately
i cut it because i the first run through
i did on this was too long
um
so what i might do just quickly is is
have a look see it um well actually i'll
show you the machine i'm using i'll go
back to my slides
and you'll be able to see the machine
that i've actually been
using here let's go back to the slides
this is the sc120c
it was designed by a
very prolific retro
brew
designer by the name of steve cummin
cousins
i've got links to all of this stuff at
the end of the slides and i will release
the slides so you can actually go and
have a look at this stuff i bought this
on tindy it cost about
the machine itself cost me
i think it was 100 220 dollars
that's a complete kit
unassembled of course the fun part is
assembling it
that's also using a floppy drive
controller that was designed
uh by
uh
scott baker
who did a series of youtube videos a
couple of years back where he messed
around and designed bits and pieces for
the rc
2014
now the se 126
is designed to to work with any of the
rc 2014 modules
so
i
bought the bits
including the board for the for the
floppy disk controller and i had a bunch
of old 1.44 meg floppy drive drives
flight around from the pc days
and
yes it works
let me show you booting from the floppy
it'll bring back memories i'm sure
and the floppy drive is this number two
that's booting
cpm
from a 1.44 megabyte floppy disk
as you can see it's taking a bit of time
and this is
another way of flashing the rom you can
boot from the floppy disk you can
actually
have the rom image on the floppy
it will fit with the flash tool and you
can then flash the the rom using the
floppy it takes a little bit of time but
it works works reasonably well
there is as i said
cpm is very useful because there is a
huge back catalog of cpm programs
most of them of course are
business-based ones like um
word star and
visicalc and stuff like that
but there is also a bunch of development
tools out there as well
z80 compile
assemblers there's a number of
compilers in fact if i remember
correctly an older version of the gcc
will actually cross compile to z80
brook z80 assembler
so
it's a very useful operating system if
you want to mess around it's very small
it can be very fast
the z80 or the z180 processor on the sc
126
is in fact running at 18 megahertz
um the rc 2014 i believe was running at
four
correct me if i'm wrong
sorry randall we're out of time time
that's fine and you have
quite a few questions in there that we
don't have time to ask right now
but
there was a very keen audience in the
chat
so if you're happy randall we'll send
you and them over to the post talk chat
kaya theater text channel in venulis
we'll copy those questions we didn't
have time for over
and i'm sure you'll have a whole gaggle
of people wanting to talk about all
those things you showed us
no worries thank you very much and
thanks everyone so much for your talk
no worries
all right um we'll be back for the next
talk after this short break
thanks guys that was good
nice one
had to drop in there at the end
yeah my medallion out