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<li><a href="/"><h1>Chrisoft</h1></a></li>
<li><a href="/blog"><h2>Blog</h2></a></li>
<li><a href="#"><h3 id="title">RBUS-ADAT devlog</h3></a></li>
<li><span>Tags</span>
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<li><a href="/blog/list/music/">music</a></li><li><a href="/blog/list/electronics/">electronics</a></li></ul>
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<li id="tocouter">
<span>Table of Contents</span>
<ul id="tocroot">
<li><a class="toctarg" href="#tocanch0">Origins</a></li><li><a class="toctarg" href="#tocanch1">Background check on the chip</a></li><li><a class="toctarg" href="#tocanch2">Ill-fated commencement</a></li><li><a class="toctarg" href="#tocanch3">Designing the board</a></li><li><a class="toctarg" href="#tocanch4">Board production and final
assembly</a></li><li><a class="toctarg" href="#tocanch5">Full project timeline</a></li><li><a class="toctarg" href="#tocanch6">Full material cost</a></li><li><a class="toctarg" href="#tocanch7">Potential future work</a></li><li><a class="toctarg" href="#tocanch8">I want one! What should I do?</a></li><li><a class="toctarg" href="#tocanch9">You’re an idiot and
your design is trash!</a></li><li><a class="toctarg" href="#tocanch10">Acknowledgment</a></li></ul>
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<li style="margin-left:-0.5em"><a id="prevp" href="2024-02-02.html">Prev post</a></li>
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<h2 id="titleh" class="TText" style="font-wight:normal;">RBUS-ADAT devlog</h2>
<div id="datetags" class="TText" style="margin-bottom:1em;">2024-02-04<br>#music #electronics</div>
<hr><div id="article" class="TText"><article>
<h2 id="tocanch0" class="tvis">Origins</h2>
<p>Funny enough, the origins of this project has nothing to do with
R-BUS <strong>or</strong> ADAT.</p>
<p>Ideas to build a digital only version of the EDIROL SD-80 surfaced in
early 2023 as an extension to my SD-80 modding plan. Beacuse my SD-80 is
half broken (headphone amp on analog output 1 fried due to my stupidity,
see my <a href="https://chrisoft.org/blog/post/2020-11-20.html#tocanch2">second
SD-80 post</a> for how it happened) and I only ever record it through
its digital outputs anyway, I believe I can drastically reduce the
footprint of it by taking out all the analog outputs and removing the
now unused ±15V rail, making the device USB bus powered at the same
time. There was also plans to add a second digital output to the modded
SD-80, however the plan was never finalized, let alone implemented
because of my lack of proper electronics knowledge and soldering skills.
The idea was therefore shelved.</p>
<p>Meanwhile in early 2022, I acquired a Roland XV-5080 (which I still
have a long overdue review to write). I was also only recording that
thing digitally and sometimes felt that wasting the other 3 stereo
outputs is a shame. I did a bit of research and apparently the R-BUS
port on its back outputs all 4 stereo outputs of the synth. Later I
found out there was the DIF-AT and DIF-AT24 that can convert R-BUS to
ADAT which is still fairly common on modern audio interfaces. However
for a small box that doesn’t really do much, asking price for the DIF-AT
is absolutely crazy – every single listing I saw was ~$200. And the
DIF-AT24, which supports 24-bit ADAT output (in contrast to DIF-AT’s
20-bit output), is pretty much unobtainium. So I decided to live with
recording through its S/PDIF output for the time being.</p>
<p>In September 2023, by pure coincidence, I found a listing on ebay of
a chip described as “ADAT optical encoder/generator”, which was the <a href="https://www.coolaudio.com/docs/COOLAUDIO_V1401_DATASHEET.pdf">coolaudio
V1401</a> that later would become the heart of my design. After reading
its datasheet I decided it would pretty much make my SD-80 digital mod
trivial, with the added benefit of carrying both stereo output channels
on a single port. So I opened up the service manual for SD-80 and
started to study which pin each signal should go to. However I quickly
realized that performing the mod would require soldering around the XV
chip inside the SD-80, which is still a thing that I’m not really
willing to do; and that I could easily test out my theory on XV-5080’s
R-BUS port because the digital audio output pins on XV-5080’s R-BUS port
is pretty much directly connected to the XV chip through an
inverter.</p>
<p>To summerize … I came up with a solution for a problem that I made up
for myself.</p>
<h2 id="tocanch1" class="tvis">Background check on the chip</h2>
<p>The seller of the chip claims the chip is an equivalent of the AL1401
from Alesis, which sounds quite interesting as Alesis is actually the
company behind ADAT (<u>Alesis</u> Digital Audio Tape, as for why it’s a
tape not a optical interface… that’s a story for another time).
Suspicion that this chip is a Chinese clone arose. So I did a bit of
background on the company … <a id="n1" href="#note1" class="note">[1]</a></p>
<p>Turns out, of course it is. While its roots can be traced to the US
in the 90s, design team of coolaudio is now located in China
<a id="n2" href="#note2" class="note">[2]</a>. Better still, it’s a brand
of Music Tribe, which is Uli Behringer’s company. Yes it’s the same
person who founded Behringer which is best known as the legal (/s) clone
audio equipment manufacturer. <del>No wonder why coolaudio’s product
portfolio is all clone chips.</del></p>
<p>Well, the original AL1401 is pretty much impossible to find nowadays,
so I really have no choice don’t I?</p>
<h2 id="tocanch2" class="tvis">Ill-fated commencement</h2>
<p>I ordered the V1401 chips before my end-of-year vacation travel. When
I returned from my vacation, I found these in my mail box:</p>
<div style="text-align:center;">
<a href="//filestorage.chrisoft.org/blog/img/rbdt-pk.jpg"><img style="width: 50%;" src="//filestorage.chrisoft.org/blog/img/ssbsthumb_1024x1024_rbdt-pk.jpg"></a><br>Suspicious packets
</div>
<p>which may look suspicious to law enforcement… but they are actually
just chips. Not the edible kind.</p>
<p>My prior experience with electronics is only limited to reading
schematics and disassembling (and destroying in the process) hundreds of
home appliances. So I guess I have seen hundreds of printed circuit
boards but I haven’t ever made or designed one of my own. I did take a
class during my undergrad that involved programming FPGAs, which did
have a “drawing schematics on a computer” component to it, but that
didn’t have anything to do with PCB design.</p>
<p>Since I do not have any prior experience working with EDA software, I
toyed with an Chinese online EDA toolkit that literally has “easy” in
its name (EasyEDA) and drew a tentative schematic for the supporting
components. Apparently it wasn’t that different from what I used when I
was taking the FPGA class, but at this stage I still haven’t confirmed
many aspects of the characteristics of R-BUS yet. As a result there were
a multitude of issues with this schematic. However it did help me come
up with a list of components (“bill of materials” in more professional
terms) needed for the project. I ordered these together with some
prototyping supplies online, hoping to actually build a prototype once
they have arrived.</p>
<div style="text-align:center;">
<a href="//filestorage.chrisoft.org/blog/img/rbdt-es.png"><img style="width: 50%;" src="//filestorage.chrisoft.org/blog/img/ssbsthumb_1024x1024_rbdt-es.png"></a> <br>The error-riddled
schematic
</div>
<p>I need an audio interface with ADAT inputs because none of the bunch
I already own has one. Since the Scarlett 18i8 3rd gen was on sale for
$360 at the time, I decided to get one.</p>
<p>When I was reviewing the datasheet for the components I ordered
<a id="n3" href="#note3" class="note">[3]</a>, I
found out that I’ve ordered the wrong optical transmitter. The part I
ordered was TOTX1353 which only supports up to 500 kb/s data rate … less
than 1/20 required by an ADAT data stream. However for some stupid
reason that I couldn’t recall, I decided to try prototyping with it
anyway.</p>
<p>I soldered one of the V1401 chips to the SOIC carrier board. As this
time I used plenty of proper, good quality flux as suggested the MacBook
repair guy Louis Rossmann <a id="n4" href="#note4" class="note">[4]</a>, the result didn’t look
nearly as bad as my previous SMD soldering attempts and I was quite
happy with it.</p>
<p>On the following day I started showing mild symptoms of a common
cold. Later that night a fever kicked in. The next day I decided to use
an expired Cornweed <a id="n5" href="#note5" class="note">[5]</a> test kit on myself and found out Cornweed was
growing inside me (hence the name of this subsection).</p>
<p>I got a week off from my workplace to get rid of the Cornweed. Since
I already felt much better after one day, I started breadboarding. It
was finished pretty quickly. But soon after that I found out there was
more than one thing wrong with the optical transmitter module I chose –
the module doesn’t have a drive circuitry built in and it pretty much
just a bare LED. There is no way in hell that it can be directly driven
from the output of a 74LS04. The LED in the transmitter only barely
lights up when the output is active. At this point I finally realized
that I can’t use this out of spec piece of crap in the final design
anyway, so I placed order for a few transmitters that are more fit for
the job.</p>
<table>
<tbody><tr>
<td>
<div style="text-align:center;max-width:98%;">
<a href="//filestorage.chrisoft.org/blog/img/rbdt-bo.jpg"><img style="width: 50%;" src="//filestorage.chrisoft.org/blog/img/ssbsthumb_1024x1024_rbdt-bo.jpg"></a> <br>The chip on its
breakout board
</div>
</td>
<td>
<div style="text-align:center;max-width:98%;">
<a href="//filestorage.chrisoft.org/blog/img/rbdt-b0.jpg"><img style="width: 50%;" src="//filestorage.chrisoft.org/blog/img/ssbsthumb_1024x1024_rbdt-b0.jpg"></a> <br>The breadboard
prototype before it was working
</div>
</td>
</tr>
</tbody></table>
<p>When I was trying to wire in the DB-25 terminal block, I found out
that I don’t have the proper flathead driver for the screws. So I had to
get one of those as well.</p>
<p>Once I really had all the items I need, I started putting things
together. The process was fairly easy but the audio interface didn’t see
the ADAT signal on the first attempt. I double checked all the
breadboard connections and inputs to the chip, which appeared to be all
correct. Feeling tired, I removed the prototype from my desk to work on
it the following day, unplugging all the cables in the process.</p>
<p>To my utter surprise, the thing straight up worked when I plugged it
in on the next day. It turns out that the port on the new transmitter is
very tight and takes quite a bit of force to insert the plug all the way
in.</p>
<div style="text-align:center;">
<a href="//filestorage.chrisoft.org/blog/img/rbdt-b1.jpg"><img style="width: 50%;" src="//filestorage.chrisoft.org/blog/img/ssbsthumb_1024x1024_rbdt-b1.jpg"></a><br>Working prototype!
</div>
<h2 id="tocanch3" class="tvis">Designing the board</h2>
<p>I decided to switch to KiCad soon after I started the actual
prototyping process, probably due to my bias towards free software.</p>
<p>Drawing the schematics wasn’t hard. Although I did have to read the
manuals to find out how buses work in KiCad.</p>
<p>There is no symbol for the V1401 chip in KiCad’s default library, and
no symbol or footprint for the optical transmitter. I had to learn how
to draw these and make them myself. Fortunately the process is pretty
straightforward and the datasheet has everything I need.</p>
<p>I spent some additional time studying the digital / analog audio
output section of XV-5080 to find out the format of digital audio data
coming out of the XV chip. Once that was done I was able finalize the
schematic. I started learning routing in KiCad soon after that. However
that effort was put on hold as soon as I realized I should really
validate the schematic on breadboard first.</p>
<p>Once I got the breadboard version working, I started working on
routing the board again. It started pretty difficult, as certain
crossings couldn’t really be avoided. However once I started making
liberal use of vias the problems got solved pretty quickly. I then
recalled seeing large ground plane on most circuit boards that I’ve laid
my eyes on and found out those can be made in KiCad with “zones”.
However for some (not completely insane, but still pretty stupid) reason
I thought adding too much copper could add to the manufacturing cost, so
I was … quite stingy with the zones. Maybe I should fix it in the next
revision.</p>
<p>Finally I added some personal markings on the board. I decided to try
the svg import feature of KiCad and drew something in Inkscape within a
minute. Once placed on the board it actually looked pretty nice. Yes it
is a Touhou reference, now stop asking why.</p>
<table>
<tbody><tr>
<td>
<div style="text-align:center;max-width:98%;">
<a href="//filestorage.chrisoft.org/blog/img/rbdt-ks.png"><img style="width: 50%;" src="//filestorage.chrisoft.org/blog/img/ssbsthumb_1024x1024_rbdt-ks.png"></a> <br>Unfinished
schematic in KiCad
</div>
</td>
<td>
<div style="text-align:center;max-width:98%;">
<a href="//filestorage.chrisoft.org/blog/img/rbdt-rt.png"><img style="width: 50%;" src="//filestorage.chrisoft.org/blog/img/ssbsthumb_1024x1024_rbdt-rt.png"></a> <br>First attempt at
routing. The board was laid out very differently.
</div>
</td>
</tr>
</tbody></table>
<h2 id="tocanch4" class="tvis">Board production and final
assembly</h2>
<p>The design was now ready and I started looking for PCB manufacturers.
I settled between a few Chinese manufacturing providers for price
considerations. My final manufacturer of choice was JLCPCB, mostly
because they have the best reviews in China. I submitted the files and
waited anxiously for the boards to arrive.</p>
<p>The boards arrived astonishingly fast. In just 5 days it went through
the entire production sequence as well as the Pacific Ocean, and arrived
at my door steps. I test fit all the components, which all fit just
fine. Next was the final assembly which also went pretty smoothly. After
a quick test the board was found to work perfectly. I was actually
shocked that the very first PCB designed by me worked first try. To be
fair the board itself is pretty simple. It was figuring out the R-BUS
protocol that made the project slightly tricky. Actually I’m pretty
surprised to find out that nobody has done the work already given the
service manual of XV-5080 has been floating around on the Internet for
many years now. Anyway, this has been a fantastic starter electronics
project for me and the process has been quite enjoyable.</p>
<table>
<tbody><tr>
<td>
<div style="text-align:center;max-width:98%;">
<a href="//filestorage.chrisoft.org/blog/img/rbdt-pp.jpg"><img style="width: 50%;" src="//filestorage.chrisoft.org/blog/img/ssbsthumb_1024x1024_rbdt-pp.jpg"></a> <br>Box from JLCPCB
</div>
</td>
<td>
<div style="text-align:center;max-width:98%;">
<a href="//filestorage.chrisoft.org/blog/img/rbdt-bs.jpg"><img style="width: 50%;" src="//filestorage.chrisoft.org/blog/img/ssbsthumb_1024x1024_rbdt-bs.jpg"></a> <br>It’s between my
fingers…
</div>
</td>
</tr>
<tr>
<td>
<div style="text-align:center;max-width:98%;">
<a href="//filestorage.chrisoft.org/blog/img/rbdt-pa.jpg"><img style="width: 50%;" src="//filestorage.chrisoft.org/blog/img/ssbsthumb_1024x1024_rbdt-pa.jpg"></a> <br>First two
components installed
</div>
</td>
<td>
<div style="text-align:center;max-width:98%;">
<a href="//filestorage.chrisoft.org/blog/img/rbdt-fp.jpg"><img style="width: 50%;" src="//filestorage.chrisoft.org/blog/img/ssbsthumb_1024x1024_rbdt-fp.jpg"></a> <br>Assembly finished
</div>
</td>
</tr>
</tbody></table>
<div style="text-align:center;">
<a href="//filestorage.chrisoft.org/blog/img/rbdt-pw.jpg"><img style="width: 50%;" src="//filestorage.chrisoft.org/blog/img/ssbsthumb_1024x1024_rbdt-pw.jpg"></a><br>IT’S ALIVE!!
</div>
<h2 id="tocanch5" class="tvis">Full project timeline</h2>
<ul>
<li>2023-09-27: V1401 chip found on ebay.</li>
<li>2023-12-09: V1401 chips bought from ebay seller.</li>
<li>2024-01-10: Schematic attempt with EasyEDA.</li>
<li>2024-01-11: First batch of components ordered.</li>
<li>2024-01-17: V1401 soldered to breadboard adapter.</li>
<li>2024-01-18: Second batch of components ordered.</li>
<li>2024-01-20: Switched to KiCad. Schematic finished except missing
symbol and footprint for optical transmitter.</li>
<li>2024-01-21: Breadboard built. Created symbols and footprint for
optical transmitter in KiCad.</li>
<li>2024-01-22: Started learning PCB layout in KiCad. First attempt to
route the PCB made. Routing halted later that day.</li>
<li>2024-01-26: First working breadboard prototype. Routing resumed and
finished the same day. Learned how to use zones in KiCad. PCB design
revised.</li>
<li>2024-01-27: PCB submitted to JLCPCB for production. 10 boards
ordered.</li>
<li>2024-02-01: PCB arrived. First board assembled and passed
testing.</li>
</ul>
<h2 id="tocanch6" class="tvis">Full material cost</h2>
<p>This includes all orders placed specifically for this project,
including stuff that can be later used for other purposes. Prices listed
before VAT.</p>
<table>
<colgroup>
<col style="width: 25%">
<col style="width: 10%">
<col style="width: 25%">
<col style="width: 39%">
</colgroup>
<thead>
<tr class="header">
<th style="text-align: left;">Item</th>
<th style="text-align: center;">Qty</th>
<th style="text-align: center;">Vendor</th>
<th style="text-align: center;">Price Total</th>
</tr>
</thead>
<tbody>
<tr class="odd">
<td style="text-align: left;">Half-size breadboard</td>
<td style="text-align: center;">5</td>
<td style="text-align: center;">Adafruit</td>
<td style="text-align: center;">25.00</td>
</tr>
<tr class="even">
<td style="text-align: left;">Breadboarding wire bundle</td>
<td style="text-align: center;">2</td>
<td style="text-align: center;">Adafruit</td>
<td style="text-align: center;">9.90</td>
</tr>
<tr class="odd">
<td style="text-align: left;">Adafruit Perma-Proto Super Pack</td>
<td style="text-align: center;">1</td>
<td style="text-align: center;">Adafruit</td>
<td style="text-align: center;">34.95</td>
</tr>
<tr class="even">
<td style="text-align: left;">Hook-up Wire Spool Set - 22AWG Solid Core
- 6 x 25 ft</td>
<td style="text-align: center;">1</td>
<td style="text-align: center;">Adafruit</td>
<td style="text-align: center;">15.95</td>
</tr>
<tr class="odd">
<td style="text-align: left;">Hakko Professional Quality 20-30 AWG Wire
Strippers</td>
<td style="text-align: center;">1</td>
<td style="text-align: center;">Adafruit</td>
<td style="text-align: center;">17.50</td>
</tr>
<tr class="even">
<td style="text-align: left;">SOIC-20 breakout 3 Pack</td>
<td style="text-align: center;">2</td>
<td style="text-align: center;">Adafruit</td>
<td style="text-align: center;">9.00</td>
</tr>
<tr class="odd">
<td style="text-align: left;">Adafruit Parts Pal</td>
<td style="text-align: center;">1</td>
<td style="text-align: center;">Adafruit</td>
<td style="text-align: center;">19.95</td>
</tr>
<tr class="even">
<td style="text-align: left;">TOTX1353(F)</td>
<td style="text-align: center;">10</td>
<td style="text-align: center;">DigiKey</td>
<td style="text-align: center;">92.88</td>
</tr>
<tr class="odd">
<td style="text-align: left;">16SEPC100M+TSS</td>
<td style="text-align: center;">20</td>
<td style="text-align: center;">DigiKey</td>
<td style="text-align: center;">11.56</td>
</tr>
<tr class="even">
<td style="text-align: left;">SN74LS04N</td>
<td style="text-align: center;">25</td>
<td style="text-align: center;">DigiKey</td>
<td style="text-align: center;">19.30</td>
</tr>
<tr class="odd">
<td style="text-align: left;">CTS 208-4</td>
<td style="text-align: center;">10</td>
<td style="text-align: center;">DigiKey</td>
<td style="text-align: center;">5.76</td>
</tr>
<tr class="even">
<td style="text-align: left;">DB25-SL-25</td>
<td style="text-align: center;">10</td>
<td style="text-align: center;">DigiKey</td>
<td style="text-align: center;">12.60</td>
</tr>
<tr class="odd">
<td style="text-align: left;">CFR-25JB-52-1K</td>
<td style="text-align: center;">100</td>
<td style="text-align: center;">DigiKey</td>
<td style="text-align: center;">2.47</td>
</tr>
<tr class="even">
<td style="text-align: left;">CFR25SJT-52-2K2</td>
<td style="text-align: center;">100</td>
<td style="text-align: center;">DigiKey</td>
<td style="text-align: center;">2.47</td>
</tr>
<tr class="odd">
<td style="text-align: left;">1N4002B-G</td>
<td style="text-align: center;">30</td>
<td style="text-align: center;">DigiKey</td>
<td style="text-align: center;">4.32</td>
</tr>
<tr class="even">
<td style="text-align: left;">25SEP10M+TSS</td>
<td style="text-align: center;">20</td>
<td style="text-align: center;">DigiKey</td>
<td style="text-align: center;">18.84</td>
</tr>
<tr class="odd">
<td style="text-align: left;">C320C104K5R5TA</td>
<td style="text-align: center;">50</td>
<td style="text-align: center;">DigiKey</td>
<td style="text-align: center;">5.05</td>
</tr>
<tr class="even">
<td style="text-align: left;">FCR684208T</td>
<td style="text-align: center;">10</td>
<td style="text-align: center;">DigiKey</td>
<td style="text-align: center;">33.75</td>
</tr>
<tr class="odd">
<td style="text-align: left;">V1401</td>
<td style="text-align: center;">10</td>
<td style="text-align: center;">ebay (av13)</td>
<td style="text-align: center;">30.00</td>
</tr>
<tr class="even">
<td style="text-align: left;">JUXINICE DB25 Male to Male Cable 3 feet,
26awg Tinned Copper Wires,Double-Shielded with Foil &Metal Braid,
D-SUB 25 pin Cable RS232 Serial Cable in Black</td>
<td style="text-align: center;">1</td>
<td style="text-align: center;">Amazon</td>
<td style="text-align: center;">12.99</td>
</tr>
<tr class="odd">
<td style="text-align: left;">Antrader 2PCS DB25 Breakout Connector
D-sub 25-pin Female Adapter RS232 to Terminal Board Signal Module</td>
<td style="text-align: center;">1</td>
<td style="text-align: center;">Amazon</td>
<td style="text-align: center;">11.99</td>
</tr>
<tr class="even">
<td style="text-align: left;">Focusrite Scarlett 18i8 3rd Gen USB Audio
Interface</td>
<td style="text-align: center;">1</td>
<td style="text-align: center;">Sweetwater</td>
<td style="text-align: center;">359.99</td>
</tr>
<tr class="odd">
<td style="text-align: left;">Mako Driver Kit - 64 Precision Bits</td>
<td style="text-align: center;">1</td>
<td style="text-align: center;">iFixit</td>
<td style="text-align: center;">39.95</td>
</tr>
<tr class="even">
<td style="text-align: left;">PCB Production</td>
<td style="text-align: center;">10</td>
<td style="text-align: center;">JLCPCB</td>
<td style="text-align: center;">14.50</td>
</tr>
</tbody>
</table>
<p>Grand Total = $810.67</p>
<h2 id="tocanch7" class="tvis">Potential future work</h2>
<p><del>First of all I need to fix the stingy ground plane.</del></p>
<p>V1401’s datasheet isn’t very clear on whether it can generate a
24-bit ADAT stream. Recordings made with the Scarlett 18i8 seem to have
the full 24-bit resolution, but that could be due to interpolation done
by the audio interface or operating system. Testing this requires an
oscilloscope which I currently don’t have.</p>
<p>It is highly feasible to implement an ADAT encoder / decoder in
software on cheap microcontrollers like the rp2040. The ADAT protocol is
documented <a href="https://ackspace.nl/wiki/ADAT_project">here</a> and
seems fairly straightforward to implement. This also has the added
benefit of making sure that 24-bit ADAT is really supported. However
this will also more than likely require an oscilloscope for debugging.
I’ll also have to learn rp2040’s PIO programming and theories on PLL
operation, both from scratch.</p>
<p>Exposing the MIDI interface on R-BUS also seems possible. However it
seems that XV-5080 doesn’t make use of the MIDI interface on R-BUS
<a id="n6" href="#note6" class="note">[6]</a>.</p>
<p><del>Maybe I’ll add more Touhou references to the silkscreen, who
knows.</del></p>
<h2 id="tocanch8" class="tvis">I want one! What should I do?</h2>
<p>First of all I’d suggest giving the <a href="https://filestorage.chrisoft.org/blog/data/rbus_adat_m.pdf">manual</a>
a read to make sure this board really does what you want.</p>
<p>If you have made up your mind to get a board, I have some bad news
for you. Unfortunately right now there’s no straightforward way obtain
this board. Mainly because I have never sold anything online. Also this
board is bound to be a very niche product, and possibly can’t even
recover the development costs if I decided to sell them. Those are the
reasons why I currently have no plans to sell the board.</p>
<p>So right now your options are:</p>
<ul>
<li>Build the board yourself. The design is fully open source and build
instruction is included in the manual. If you are comfortable with
electronics DIY projects, this is probably your best bet.</li>
<li>Let me know you want one! Right now I still have a few
pre-production boards lying around. As long as you’re willing to cover
the terrible USPS shipping rates I’m willing to assemble a board and
send it your way. Of course you’re welcome to pay a little bit more… but
any excess for now will be treated as donations (a “pay what you think
it’s worth” model) – as I don’t have pricing fixed yet. Also if enough
people have expressed interest in the board I might actually start
selling them…</li>
</ul>
<h2 id="tocanch9" class="tvis">You’re an idiot and
your design is trash!</h2>
<p>First of all, thank you. I am indeed a massive idiot.</p>
<p>If you have suggestions on how this board could be improved, please
consider sending them to me. As a beginner in electronics design I can
definitely use any piece of advice coming from pretty much anyone in
this field. Any constructive suggestion will be greatly appreciated.</p>
<p>Of course other types of contributions will also be appreciated. For
example this board currently lacks any kind of enclosure as I have zero
idea how to create 3D models for real-life object manufacturing. Help in
this space is desperately needed.</p>
<h2 id="tocanch10" class="tvis">Acknowledgment</h2>
<p>I’d like to thank <a href="https://www.youtube.com/@KRPalto47">Palto</a> for being extremely
supportive towards this project, including putting up with my endless
DMs on Discord.</p>
</article>
</div><br><hr>
<div class="TText" id="notediv" style="font-size:80%;"><span class="TText"><a id="note1" href="#n1">[1]</a>: Not to shit on the country or
anything, after all I’m from said country … but Chinese clone chips are
notorious for being unreliable in general or straight up not
working.<br></span><span class="TText"><a id="note2" href="#n2">[2]</a>: <a href="https://www.coolaudio.com/aboutus-page.php">“World
Class Management &Technical Team: One of the most extensive design
service companies in China”</a><br></span><span class="TText"><a id="note3" href="#n3">[3]</a>: which is probably a dumb thing to do. I should have read
through all of them <em>before</em> placing the order.<br></span><span class="TText"><a id="note4" href="#n4">[4]</a>: He doesn’t really do the repairs
himself nowadays any more, does he?<br></span><span class="TText"><a id="note5" href="#n5">[5]</a>: That thing which destroyed 2020 to 2022
for countless people misspelled deliberately to avoid unwanted
attention.<br></span><span class="TText"><a id="note6" href="#n6">[6]</a>: See the section on XV-5080 in RPC-1’s manual.<br></span></div>
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