Zumspot & MMDVM Demo page

Some information on the Zumspot project & MMDVM demos.

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ZumSpot and MMDVM NEWS:

In a post about 2 paragraphs back you might have seen the newest Raspberry PI, the 
Pi- Zero(w).  It's also the smallest and cheapest at less than $15 cdn.
For a mobile/portable hotspot its great to have the Zumspot Rpi UHF board plugged in on top.
Zumspot Rpi with RPi-Zero(w)
Running the very popular PI-Star software that runs the Pi headless 
with WiFi as this uses a web brower.
Here is my RPi-Zero(w) with some accessories used for testing on the bench.
A HDMI-mini adapter for the monitor, a micro-to-USB adapter connected to a USB-Ethernet bar.
The latter give me ethernet plus 3 full sized USB ports. For USB-Nextion LCD, for USB-BT dongle
for a keyboard, and this case a USB to my Zumspot board.(Right-click then View Image for full size)

RPi-Zero(w) with accessories

Well Bruce Given (VE2GZI) and the ZUM team keep cranking out new harware. No wonder there is always
a lineup. Their latest device is the ZUM STM32 Radio-Modem-v0.9. Similar to the very popular 
Zum modems v1.0 and 1.01 (which I have both). However, no more Arduino-DUE required.
Instead this new board already has a STM32F446 CPU. The STAT Green LED blinks fast to show its
running the familiar MMDVM firmware, already pre-loaded. This board is also a Pi-HAT,
so it plugs into the RPi GPIO pins for a clean and neat package. I have it on a PI-2
since it will be fixed as a base hotspot or repeater with wired ethernet.
Instead of manually editing a bunch of scripts and .ini files, I used the amazing PI-Star
image which lets you setup everything from a remote web browser. The new hardware is
already on the list of devices in Configuration.
The only thing I did locally was use my Nextion LCD display to monitor the live RX BER
readout when I was adjust the RX level. The multi-turn pots (they're CCW) make fine
tuning of RX and TX levels easy. From D-Star, to DMR and C4FM I was able to get very
low BER in all modes when using just an old analog Kenwood radio (with TONE input).
Here is the new modem board in action.(Right-click then View Image for full size)
ZUM Modem STM32

Just as I finished this one, another piece of ZUM hardware appears. Following the Zumspot that I
reviewed here earlier, is a new RPi-HAT version. It plugs into the GPIO pins of a Raspberry PI and
has the familiar 10mW xcvr for D-Star, DMR, Fusion and P25 modes. (Like DVMega)
ZumSpot RPi Board
In the brochure it's shown connected to a Pi-Zero-W. When the Raspberry Pi's first came out, people said,
"no way..a computer for $35?". Well the Pi-Zero is scaled down from the Pi2 or Pi3 but does the job
for Hotpsots, especially with Pi-Star software that runs headless and no GUI. Its a hot item right now
at $10 US, for the Wifi version. Note it has mini/micro versions of HDMI and USB port (1) and no
ethernet. Also a single CPU with 512MB RAM...kinda like RPI B+.
Now back to the ZumSpot Hotspot Board. More about it on the MMDVM FB pages:
MMDVM Facebook Page.
MMDVM ZumSpot Facebook Group

Updates to Pi-Star software continue to make this a user-friendly package. The "One-Click"
Update function works very well. Saves a lot of downloading, compiling and editing.
One thing that is not all that easy to do is firmware updates. 
Every time there is a new DV device, its not long until its firmware needs updating 
either for fixes or new features. Usually this is a tricky task that sometimes involves 
mods to the hardware (solder jumpers) or to install complicated software. 
For the Zumspot it turns out to be somewhat easy since we don't have to actually 
compile the firmware. The latest binaries and the uploader are on this website.
The program ZUMSpotFW_setup.exe can be used to upload the compiled binaries by just plugging
the Zumspot into a USB port on your PC. 
Now my Zumspot has the latest firmware:
MMDVM protocol version: 1, description: ZUMspot ADF7021 v1.0.0 20170728 (DStar/DMR/YSF/P25) GitID #c16dd5a

I'm running a new image called PI-Star.
It supports all of the MMDVM features and works great on a headless Hotspot.
Testing of this new image on both the Zumspot and DVMega was very easy.
The web based configuration is easy to understand and use.
It appears to support all the modes, hotspots, and server combinations from the
drop-down lists. 
Here is the list of devices currently supported:
Pi-Star hardware list

I like the one-click backup feature that sends you a zip file. 
The MMDVM project has new features almost every month so updating your system has 
been a chore. This package does it easily. Even when there is a new image you can 
use your backup file to get up and running quick and easy.

Since PI-Star has no GUI, the image file is small and will fit in 2GB. I had an old 
4GB SD that I replaced from my GPS and it worked great on that. Of course finding 
4GB or even 8GB SD cards is rare now. It supports the Nextion LCD display on USB,
which makes a great monitor facility.

The Raspbian based image runs in read-only mode to help reduce SD problems on 
power-down. Of course you can Reboot or Shut-down from the web dashboard.

Anyway, have a look at this image. The only downside so far is very little documentation, 
and support is only from a FaceBook Group, PI-Star FB Support Group.

One thing that is a bit of a problem is getting the Wifi setup. There are two ways to do this.

1. Plug your RPi into ethernet and let ethernet DHCP pickup an IP. 
Connect an HDMI monitor and a keyboard to your RPi, login as user "pi-star" (raspberry), then run "ifconfig".
You will see the ip address given to the eth0 port. 
-or- Browse to your home router and lookup the DHCP table to see what IP was assigned to device "PI-Star"
Then use a web browser on a computer to connect to
that address and you will get the Pi-Star dashboard and Config page. 
-or- If you want to run 'headless', you can wait a minute or two, and the RPi will broadcast its hostname as "pi-star".
Your computer's web browser should then be able to connect to  http://pi-star without knowing the IP address.

From here you can do all the config setup, including the WiFi. 
When you are done, do a Backup from the Configuration tab. That saves the complete setup into a dated .zip file that
you save on your local computer. Now you can Reboot the Pi from the Power tab. 

Remove ethernet cable and you should be on the Wifi.
Watch the HDMI monitor and it will give the new Wifi IP address, use that in your browser for the
dashboard from now on.

2. You can do all the configuration offline on your own computer by editing the text files that are used
in the Backup/Restore process. I can supply a clean setup set. If its just the Wifi you need then edit just
the wpa_supplicant.conf file.

As the author says in this note, you can load the backup .zip file on the "boot" section of the SD card and it
will load on startup.
From Andrew Taylor:
     You use the image writer to burn the image file to the SD card, like you have done before, at the end of that process, 
     a new drive called "boot" will appear on your system, you drop the config zip (that you get from backing up your config) 
     onto that boot drive before ejecting the SD card.
     Then boot the Pi up with the newly written SD card and it will load the settings from the config zip file.

Here is a screenshot of my PI-Star dashboard running with my dual-band DVMega on BM-DMR.
(right-click and View Image for full-size)
PI-Star Dashboard VE1AIC Hotspot

Today I received the latest project from the MMDVM team.
It's called the Zumspot Libre Kit and is available from Bruce Given of MMDVM Fame.

Oh...you many be wondering just What is this device and What can it do.

This kit has a UHF tranceiver (10 mW) and a STM32 micoprocessor board soldered into a
carrier board with LEDs for status. The micro has a uUSB port that connects to a
Host computer (like a Raspberry Pi) running MMDVM_Host software.
This produces a UHF low-power Hotspot for Digital Voice modes D-Star, DMR, Fusion 
and P25. You can find some info on the kit at the  MMDVM Facebook Page.

This image is from the Facebook page and shows the components provided.
Zumspot Libre Kit
Quoting from a post on the FB page:
Kits comes with 
1. Carrier board
2. Modified 7021 Board with Correct TCXO 
3. Modified STM32F103 board so it will work with 
all USB interfaces.
4. 14 LEDS ( So you can use some colors twice ! )
7 Resistors
6. Bootloader preprogrammed on the STMF103 board
7. Antenna
Cost will be $85.00USD plus shipping
You just need basic thought hole soldering skills

p.s. the kit also comes with a ST-Link device for updating the micro's firmware. 

When assembled it will look like this (mine).
My complete Zumspot
(Right-click and View Image for full size)

It should only take about an hour to solder in the few components. You have twice
as many LEDs provided so you can decide on your choice of colors. 
(More about that later in my hints & notes)

The kit does include some Assembly Instructions (Rev 1.00 May-7-2017).
 Here are some of additional notes from my kit.
  Page 3.1, and page 4: Add jumper to RF7021SE board
  - There are two solder pads that are used as jumpers, bridge the gap on the
   jumper across from the "RXD" label. Circled on diagram page 4.
	 (Also as shown in picture below)
3.2 Install LEDs.
  - The kit contains 7 bags with 2 LED's each. Easy to tell the color on the bags
	with the dot (Yellow, Blue, Green, Red) but the others are labled as
	"P" - Purple, "O" - Orange, and "M" - White (monochrome?)
  - Here is what I selected for the color layout:
	1. DMR    - White
	2. D-Star - Orange
	3. YSF    - Blue
	4. P-25   - Purple
	5. PTT    - Red
	6. COS    - Yellow
	7. PWR    - Green
- One other thing I added was a rubber pad below the RF board, and small ty-wraps
to hold the end in place. This takes some strain off the connectors.
Zumspot RF pad
The STM Micro is already programmed with MMDVM code so its ready to run.
Just connect the uUSB port to a Raspberry Pi with MMDVM_Host and you're away.
This unit will also support the Nextion display (shown on top of a Pi-3).

My final image shows the Zumspot in operation.

Zumspot in operation

Here are some comments about verifying the operation of Zumspot.
When you power on your RPi with the USB connected, the carrier board's PWR LED should light. 
The STM Micro board will light its Green Pwr LED as well. Since the STM has MMDVM 
code it will run that and display a blinking Red led. Blink rate about once per second.
When you start MMDVM_Host, on the RPi, it will connect to the Zumspot board and report like this:
YYYY-MM-DD HH:MM:SS MMDVM protocol version: 1, description: 
MMDVM_HS-ADF7021 20170414 (D-Star/DMR/YSF/P25) (Build: 20:42:31 May  5 2017)

This verifies the MMDVM_Host is talking to the STM Micro and shows the firmware version/date.
At this time the STM Red led should blink rapidly, about 2 times per second.
At idle, the carrier board only has the PWR led lit, but other led's will come on as it's
status changes. If you key your radio the COS led should light and the corresponding
Mode led should also light and stay lit for about 5 seconds after the Zumspot returns
to idle. This occurs even though you may have enabled only one mode.
When the Zumspot transmits, the PTT led comes on, and again the led for the active Mode.

So, if you're just starting out with Zumspot and have no previous experience with
MMDVM, then I recommend you research what others have posted about MMDVM projects.
In particular notes about the DVMega setups which would be nearly identical.
There are a number of SD card images that have been prepared which make it very close
to plug and play.  The only changes to files for the Zumspot compared to a DVMega is
the [Modem] section of MMDVM.ini, since this is an external USB device. 

# ZumSpot on Pi3

Good Luck, and Have Fun.
Any Questions should be posted on the MMDVM Yahoo Group.


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