NVMe discs, Dual boot on Pi4, Family Trees, GPS Unit

RISC OS London Show

What's on show?

Most of my RISC OS machines expect a wired connection for their network so this time I have connected them in this way to simplify setting up and to demonstarte a wirelless extender. This allows me to plug in an IP phone and make calls from my Bristol number (0117) whilst in Harrow.

I shall be handing out some free software on USB sticks at the show with the latest version of !FamTree as well as a RingBind version of the RISC OS 5.30 User Manual and both RingBind and PDF versions of the Impression User Manual. At least until stocks run out - that's the first sixty customers...

This amounts to over 242M bytes of data all on a 128Mbyte USB stick.

Real Time Clock

There are a few machines that do not have a real time clock, including the Pinebook Pro, Hydra and Raspberry Pi. One solution is a GPIO-connected RTC board (e.g. CJE micros) and some machines have a real time clock chip on a GPIO bus that RISC OS cannot see (Pi Foundation IO board, Waveshare IO board). Another solution is a USB-connected real time clock with software in the boot sequence to read it and an application to set it. Various solutions are on display at the show. This was described in an article in Archive 28:1.


This device is a SB Components USB-RTC module using a MCP2221 to provide an IIC bus for a DS3231 RTC at address &68 - this can be connected to one of the four pin USB headers on the Super6C motherboard on the Hydra or plugged in to a USB socket on any computer.


The software to control the USB-connected RTC board. The zip archive RTC/zip‘ contains a utility !4thDim in PreDesk which will set the RISC OS time from the USB-RTC registers if one is fitted and contains plausible data. The other utility SetRTC‘ allows the initial setting of the USB-RTC. The battery will then keep time until power is restored.

On machines fitted with a RTC that RISC OS cannot see but Linux can (e.g. Pi Foundation IO board, Waveshare IO board, DeskPi Mini) this avoids the issue where Linux and RISC OS assume a different datum for 'time zero' (1970 versus 1900) and write different values to a real time clock chip.

Also on show is a DeskPi Mini with a real time clock board plugged in to the GPIO pins. This machine also has an NVMe drive partitioned to 768GB for RISC OS and 300MB (Linux boot) and 20GB (Linux root). A push button determines whether the machine starts up in RISC OS or Linux.


A custom PCB plugs in to the back of the DeskPi with a socket for a RTC board and a push button to select RISC OS or Linux. Inside is a 1TB NVMe drive partioned to support both RISC OS and Linux.

NVMe drives

It is now easy to fit an NVMe drive to work under RISC OS and the Waveshare IO board or the DeskPi Mini or the Hydra provide a good foundation for this. As a DIY solution the Waveshare IO board is on show with some extra hardware to provide both a RTC and fan control software.


Here are the bits! A custom RTC/fan board, a Waveshare fan, the Wavehsare Mini-B IO board with 4GB CM4 and another Mini board (actually an A) with an NVMe drive plugged in.


All assembled: adding the fan takes the height from 18mm to 22mm and the custom board increases this to 25mm. It is all a bit of a snug fit!


The CM4 can barely be seen beneath the fan and there is only just space to fit in the circuit board and the 4-pin fan header (top left of the circuit board). The CJE RTC module is moved just far enough away to clear the fan housing and mounts on a 2- and 4-pin header.. The EMC2101 board mounts on a 2- and 6-pin header. The 4-pin header between them (and the 6-pin DIL header) support the circuit board itself. Underneath an NVMe drive is plugged in to the m.2 socket.

Sat Nav

The SatNav software has been updated so that it can receive navigation data from a USB-connected GPS unit. This is important because purpose-built units that can function as a navigation device are rather limited in what they can display. A portable computer with monitor, battery etc. all built into a compact case, with a GPS unit plugged in to one of its USB ports can now display a map of where you are. A Pinebook Pro running RISC OS with SatNav and RiscOSM will be on the stand.


The Pinebook Pro screen showing SatNav 2.54 running with a USB GPS device that cost about £15 from Amazon. The yellow dots show the position in the sky for each satellite that can be seen (North at the top, horizon at the circumference and the central dot is overhead). On the map the GPS symbol shows position and bearing, just West of North and the bearing is repeated as a red dot on the SatNav window and as a red pointer on its icon bar icon. Only four satellites are being tracked because the GPS unit is on a table about 12 feet from the window. In the open air with a clear view of the sky it would be tracking more than four satellites.

The SatNav unit has been updated: with the hardware design now stable the previous 'breadboard' approach has been turned up a notch with a purpose built circuit board, seen here with the components soldered onto it. It has four sockets for the four modules: OLED, power, ADC and GPS.


The unit has been tested and works, adapting itself to the modules it finds to be present.

The printed circuit boards will be on sale for £10 each, complete with full instructions for building your own GPS unit.

Also on sale, for £25, will be a User Manual (printed in full colour) for Impression covering Style, Publisher and Publisher Plus - the few sections of the manual which cover features not present in Style are marked. Provided with the manual, courtesy of ROD, is an exclusive download link for the Impression Publisher Plus software at version 5.13, the last version issued by Computer Concepts. This represents extremely good value for money.


Only £25? For a full colour printed manual and the software iself?

Another manual on sale is the guide to the other software provided with Impression: TableMate, Equasor, Wordworks and SepEd2. This manual is on sale for £12 - it is printed in full colour. Both manuals have been completely upgraded to show screen shots on current machines.


The manual is shown with handy tabs to jump to particular sections.

Now for a bit of a gimmick - also on show is some software, RingBind, which will display a manual on the desktop as if open on the table. As each page is turned, an animated view of it turning is provided. One example provided is the current RISC OS User Manual, now released under the Apache licence. Full instructions for converting your own manuals are provided.


The current User Guide for RISC OS 5.28 is shown here with the animation, with handy tabs to jump to particular sections.

A printed copy of the User Manual for Impression-X (and Style and Publisher) will be on sale at a special show price of £19 (it is normally £29 inclusive of P&P) - purchasers of this manual will also get an exclusive download link for the Impression Publisher software. This is a bargain price for an excellent desktop publisher package. The printed manual for the 'add-ons' Equasor, TableMate and WordWorks priced at £12 has SOLD OUT.

My !FamTree software will be demonstrated at the show. It was priced at £15 but is now FREE and allows a graphical family tree layout to be produced.

I had the idea that relationships could be defined by means of the directory structure: each directory would represent an individual or couple and there would be a sub-directory for each child of the relationship. A tree‘ structure could then be produced, arranged vertically. Each directory would contain a text file providing the detailed information that would appear in the box and I would arrange some form of editing on screen to move the boxes around to make best use of the space.

When this directory structure is loaded into the application !FamTree, a draw graphic of the implied family tree is produced with the boxes widely spaced to be out of each other‘s way. This is shown in a work area window and will recognise mouse clicks on the individual boxes interpreting such clicks as demands to move left or right. With SHIFT held down, the movement is up and down. Holding CTRL as well magnifies the movement. After a little bit of editing, the graphic appears as given below. It uses space economically allowing a quite complex family tree (going back to 1750) to be created on 297mm x 1200mm paper, which I can print on my A3 colour laser printer.

The FamTree application also supports the import of files in the standard GEDCOM 5.5 format.

GPS Unit

I'll also be exhibiting the latest version of my SatNav application now running in a 3½″ x 2¼″ x 2″ box with a small internal battery which can float charge itself if an external battery or other 5V power source is attached. Although I will have a monitor connected to this device at the show showing a full RISC OS desktop with both SatNav and RiscOSM running, the unit is designed to provide sufficient information on an OLED display and an optional electronic-ink display.


The box is now pocket-sized.


A trip from Bristol to Milton Keynes was recorded using SatNav in GPX format and then passed to RiscOSM for analysis. The logging included information in the format below:

<trkpt lat="51.48479185" lon="-2.612334261"><time>2017-10-06T09:18:18.56Z</time><extensions><satnav:odo>2183</satnav:odo><satnav:dxy>10/26</satnav:dxy></extensions></trkpt>
<trkpt lat="51.48522501" lon="-2.611908333"><time>2017-10-06T09:18:29.00Z</time><extensions><satnav:odo>2240</satnav:odo><satnav:dxy>29/48</satnav:dxy></extensions></trkpt>

Development

The development of this project has been described in Archive magazine:

At the show you can see that a power boost board has been added to extend battery life, software-controlled power switching has been added (either using 'on' and 'off' push buttons or a Witty Pi and real time clock/alarms) and GPX logging has been added to internationalize Satnav, now at version 1.90.


The power boost board allows an internal 3.3V LiPo battery to be float charged by an external 5V powerbank or mains adapter. It produces an output of 5.2V from either the internal battery (3.3V) or the external power supply (5V), whichever is the higher voltage and will float charge the internal battery from the external source. If the internal battery becomes discharged or the external ENABLE line goes low, the unit will turn off.


The power control circuitry on the ProtoPAL board. The ‘on’ and ‘off’ buttons cause q and /q to change state. The ‘on’ button forces /q to go high (provided the ‘off’ button is open circuit, q will then stay low forcing ENABLE high). This turns on the power. During the boot process GPIO 4 is set to active output high. Holding the ‘on’ button down causes GPIO 19 to be low (which can be read by software, for example to download the log) and will light the LED if Vs is 5V - i.e. if there is an external power supply connected.
The ‘off’ button forces q to go high (provided the ‘on’ button is open circuit, /q will then stay low, which can be read in software via GPIO 26). With q high, this allows GPIO 4 to control the ENABLE signal: unless GPIO 4 is active output high, ENABLE will go low, turning off the power.
Once the ‘off’ button has been pressed, GPIO 26 will remain low, will be read by software, logging will be completed, the displays updated and a shutdown/restart cycle will be initiated. This updates the CMOS ‘last on’ time so that any subsequent start up will be with a time and date no earlier than this. The restart cycle resets the ROM modules, returning GPIO 4 to inactive and thus removes the power.

Making the breakout board is a bit fiddly. The first step is to wire up the board and test for shorts:


then carefully solder on the 74HC00 chip:

The ProtoPAL board now plugs onto a Pi model A+ and has a header for a PaPiRus display. Five flying leads, plus power and ground, are then soldered as in the diagram below:

the wiring diagram for the ProtoPAL board.

And just when I thought I had finished, the ProtoPAL board is discontinued. So here it all is again on a smaller breakout board. First solder on a few wires:

Then a few more, finishing off with a few diodes, resistors and a 74HC00 chip:

so that it looks like this design layout:

and here it is, fully functioning:

it has magnetic feet, a PaPiRus display on top, with OLED and GPS module on the front face.

a view from the rear, showing the power meter, sockets for USB, HDMI and a mains adapter or supplementary powerbank and the 'on' and 'off' push buttons.

A simpler and smaller unit without the power meter and the PaPiRus display. Is this the smallest RISC OS portable? The battery life is over 12 hours in a case 90mm x 60mm and 50mm high.

Testing the small unit in a short car trip shows the unit acting as a speedometer. The NMEA sentences it uses to derive its position are also shown - the demonstartion is running at about the correct speed with updates about every 2 seconds (the NMEA data are updated every 2s). The serial data arrive with no handshaking so occasional errors occur - thus the display may occasionally blank out (as it will have no new NMEA data to log and thus think it is lost or in a tunnel).

What you would see if you had RiscOSM running as well as the unit showing the speed on an OLED display. NMEA messages are also shown but you would not normally see these.

Loading the 'gpx' file log from the unit and analysing it in RiscOSM gives the results below:

RiscOSM 1.45 analyses the log file for the journey but speeds are a bit spiky.

RiscOSM 1.50 analyses the log file for the journey much more accurately now.