Posts on Bytestone Blog

Archiving family photographs: a format statement

Tue, 20 Oct 2026 00:00:00 +0000

What we capture when we scan a family photograph, what we keep, and how we expect it to still be readable in fifty years without any of the software that made it.

GoNIX and gokrazy: two ways to run Go on bare Linux

Tue, 13 Oct 2026 00:00:00 +0000

Both put a Go userland on top of the Linux kernel, but one wants to be a small UNIX you can read in an afternoon and the other wants to be an appliance with nothing you don’t need.

An Elitech temperature logger without the manufacturer's software

Sun, 27 Sep 2026 00:00:00 +0000

Buying an Elitech RC-5 USB temperature logger and writing the software for it in Go, without ever opening the manufacturer’s web site.

ABNF and Plain Text Accounting

Sat, 14 Mar 2026 00:00:00 +0000

Plain text accounting is a useful way to describe a machine and human readable accounting journal. Some formats are single file format and some are multiple file formats. F

The software primarily Beancount and ledger transform the data into useful reports as well as validating that the data is correct in the first place.

The reports that can be run are:

Summary balances at varying times and selections. Hierachical accounts can be consolidated
Ledger entries by account
dealing with multiple commodities eg multiple currencies and stocks and shares
preparing balance sheets
preparing profit and loss
SQL like query languages
gui visualisation eg FAVA for beancount.
integration of documents into the accounts.

Beancount documents that the clear process of converting text based records to an internal memory model is:

Dates, Times and Periods

Mon, 02 Mar 2026 00:00:00 +0000

I want to write about the dates times and periods including how these are represented in text.

ISO8601 or RFC-3330 is a good place to start as UK goverment writes in their article on [dates and time-stamps standard][].

We normally differentiate between periods of time with a start and end date. Eg a week goes from Mon to Sunday where in a precision of days Mon is the start and Sunday is the end. Often we are less precise and just use the whole period, eg this will be done in week 44.

Claude, Singularity Postgres and Gokrazy

Sat, 07 Feb 2026 00:00:00 +0000

Claude, Singularity Postgres and Gokrazy

Gluten Free loaf

Fri, 02 May 2025 00:00:00 +0000

A gluten free loaf in a bread machine

Augmented Backus Naur Format

Sat, 15 Feb 2025 00:00:00 +0000

A comparison of ABNF and EBNF notation systems

Plain text accounting

Fri, 22 Nov 2024 00:00:00 +0000

Time series functions

A time series is a function that varies over time. For example the amount of money in a piggy bank. This has a value at a point in time as well as changes. This corresponds to a derivative although typically the changes are stochastic not a regular time intervals. There is also an integral version which is the change during a period eg how much was added during 1 week or some other period. Here the period can be regular.

Gokrazy WSL and photos

Sun, 28 Apr 2024 00:00:00 +0000

Very excited to be getting gokrazy to work as a deployment platform for devices. My first project is to use our Samsung smart screen as a photo display.

It has taken a little while to work out how to use effectively use gokrazy from WSL and here are some of my notes.

When building the initial image you can use gok -i hello overwrite --full x.img --target_storage_bytes=1258299392 to output to a file rather than a device which allows you to export the img from from wsl and burn on Windows. Attaching an sd card to the WSL instance I found tricky.
To cross compile and update I used CGO_ENABLED=0 GOARCH=arm64 gok -i hello update for a raspberry pi 3B+.

Solved Problems

Using Task to store required cross compile flag configuration.
Changing DNS server on router to change DNS entries of DHCP names.

Current Problems

Monitor fails after a time on my Samsung 95Q55 screen.

It works after uploading but then goes to a state overnight (power saving ?) which the TV doesn’t recognise.

Accounting for Programmers

Wed, 17 Apr 2024 00:00:00 +0000

An introduction to accounting for programmers.

EBNF Extended Backus Naur Format

Thu, 04 Apr 2024 00:00:00 +0000

Introduction to EBNF

EBNF and Participle

Tue, 14 Nov 2023 00:00:00 +0000

Using Extended Backus-Naur Form (EBNF) notation and how the Participle parsing library leverages it for elegant language processing.

HTMX applications

Fri, 10 Mar 2023 00:00:00 +0000

I have been wondering about finding a simpler development environment that allows me to do graphic programming. My first successful tool was Delphi which allowed me to generate tools with a simple Pascal like language and a great IDE. The interface was the simple VCL ([Visual Control Library][]).

[Visual Control Library]; https://docwiki.embarcadero.com/RADStudio/Sydney/en/VCL_Overview

Over time I have moved languages and currently I like writing in Python for expressiveness and Golang for simplicity and robustness.

Go CAD versions

Thu, 23 Feb 2023 00:00:00 +0000

I am keen to try out writing and designing in go CAD models. I am on a drive to simplify and unify my coding styles. My process for designing I would much rather be creating my models by programming. So I started with OpenScad. I discovered that as the models got very complicated it would start to have problems particularly with the difference function.

There was a great go library called ghostscad that generated OpenSCAD language but as it transpiles to OpenSCAD it suffers from the same problems as complexity increases. As of Jan 2025 OpenScad has more or less stopped being updated with the latest release in 2021. There is some work still going on though.

Colour Calibration

Mon, 02 Jan 2023 00:00:00 +0000

Standards

I used to have a Greta Mcbeth colour calibration both small and large but lost the large one and only have the small one left. Just recently purchased the Datacolor SpyderCheckr| 24 but probably should have bought the| 48 patch version in a hard shell. I have just discovered that| 24 patch is the right side of the| 48 patch. So can use the calibration data from that for checking the DataColour Print.

What is Tartan?

Fri, 21 Oct 2022 00:00:00 +0000

Tartan or checked weaving pattern has ancient origins. Perhaps it came with the spread of the ancient Bronze age Celts from Austria and Turkey. To the East there may be a link to the Tarim Mummies as was popularised by Elizabeth Barber¹. This currently has got caught up in origin stories of the Han. Notable mummies are the tall, red-haired “Chärchän man” or the “Ur-David” (1000 BCE); who wore a red twill tunic and tartan leggings. Elizabeth Barber highlights the similarities between this and fragments recovered from salt mines associated with the Hallstatt culture.

Filing MicroEntity Accounts

Thu, 20 Oct 2022 00:00:00 +0000

Filing microentity accounts

This is meant to document how to use HMRC’s service to input accounts and company house data when using Beancount and HMRC.

Get Beancount up to date
Generate annual accounts by editing report
Input data here by hand

Opening questions

These are the questions and the answers to which this process applies.

What is your organisation?
- Company
Do you want to make changes to a Company Tax Return you’ve already filed?

Drummonds New Bruce 1819

Sat, 18 Jun 2022 00:00:00 +0000

“XR#D40000; A#5C8CA8; HG#285800; DP#440044;”,“XR/12 DP2 XR4 DP4 XR64 A2 XR4 DP16 XR4 HG4 XR4 HG48 XR4 DP4 XR/12”

Carbon Capture for lawns

Fri, 10 Jun 2022 00:00:00 +0000

I have a robot mower that mows my grass. I was wondering if it actually captures carbon.

I can see that the soil is capturing soil as it is getting higher. I had an edging made of bricks and over the last 15 year the grass has crept up ca 15cm. So about 1 cm a year capture. This is a capture of carbon but need to do the calculations to see if overall positive.

Drummond of Megginch Tartan thread counts

Fri, 10 Jun 2022 00:00:00 +0000

Given thread counts produce table

Wait for this to come out

test = "R14 DB2 R4 DB4 R70 LB4 R4 DB20 R4 G4 R4 G74 R6 DB4 R12"

import re

PATTERN = re.compile("([a-zA-Z]*)(\d*)")

def split_thread(threadcount):
 """Given a thread count such as R14, will split to R and integer 14"""
 match = re.search(PATTERN, threadcount)
 if match:
 return match.group(1),match.group(2)
 return threadcount,""
 

class Stripe:
 def __init__(self, short_colour, count):
 self.short_colour = short_colour
 self.count = int(count)

 def __str__(self):
 return f"{self.short_colour}{self.count}"

class Tartan:
 def __init__(self):
 self.stripes = []
 
 @classmethod
 def from_space_threadcount(cls, threadcount):
 tartan = cls()
 threads = threadcount.split(" ")
 for thread in threads:
 colour,count = split_thread(thread)
 tartan.stripes.append(Stripe(colour, count))
 return tartan

 def __str__(self):
 s= ""
 for stripe in self.stripes:
 s += f"{stripe} "
 return s

 @property
 def threadcount(self):
 tc = 0
 for stripe in self.stripes:
 tc += stripe.count
 return tc

a = Tartan.from_space_threadcount(test)
print(f"Pattern = {a}")
print(f"Num threads = {a.threadcount}")

Pattern = R14 DB2 R4 DB4 R70 LB4 R4 DB20 R4 G4 R4 G74 R6 DB4 R12 
Num threads = 230

Creating images

My first attempt at creating images was using a simple turtle graphics package:# Free after the example from the Python 3.5 manual

Details of New proposed Tartan

Wed, 01 Jun 2022 00:00:00 +0000

The following is a picture of the proposed new tartan sample.

Name	Sum	R/i	DB ii	R iii	DB iv	R v	LB vi	R vii	DB viii	R ix	G x	R xi	G xii	R xiii	DB xiv	R/xv
1849 Kilt		14	2	4	4	70	4	4	20	4	4	4	74	6	4	12
1997 New Kilt		18	2	4	4	64	4	4	20	4	4	4	62	4	4	10

Drummonds of Megginch Tartan Notes

Sat, 28 May 2022 00:00:00 +0000

Drummonds of Megginch Tartan

Originally written May 16, 2018

There has long been confusion about the tartan for the Drummonds of Megginch. This is due the tartan being very similar to the New Grant tartan that was recorded by Wilson in the 1819 weaving pattern book.

Drummonds of Megginch Tartan different from Wilson Grant pattern.

The earliest example I currently have of the tartans that the Drummonds of Megginch is a kilt dating from 1849 which I wore from about 1975 to 2000. The picture is of the inside which has faded less the outer. I can be confident of the date as there is a picture of JMD (James Murray Drummond) wearing this with a sporran which I also have. The sporran was made in 1849 in Edinbugh and can be dated from the silver makers mark.

Old Plaid

Sun, 22 May 2022 00:00:00 +0000

Old Plaid

Detail of Tartan

This was one of the est unfaded squares.

Then there is the fine detail:

This for part of the tartan gives a thread count of:

Name	R/i	DB ii	R iii	DB iv	R v	LB vi	R vii	DB viii	R ix	G x	R xi	G xii	R xiii	DB xiv	R/xv
1849 Kilt	14	2	4	4	70	4	4	20	4	4	4	74	6	4	12
1820 Plaid	26	2	6	6	126	6	6	38	6	6	6	130	10	6	18
1820 scaled	13	1.3	4	4	84	4	4	25.3	4	4	4	86.7	6.7	4	12

The 1820 plaid is the original pattern scale by about 50% and then rounded.

Converting from Xero to Beancount

Mon, 28 Oct 2019 00:00:00 +0000

Converting from Xero to Beancount

This is about the journed of converting from Xero to Beancount. This version is a scrappy version written for me. The reason is cost, I need to reduce my costs to the absolute limit and can no longer afford the ca£45 for the monthly fee.

Plan

Install Beancount
Repeat the following a few times until it works well
- Export Data from Xero, CSV
- Massage
- Convert to Beancount

success criteria

Outdoor cabling and wiring standards

Wed, 05 Dec 2018 00:00:00 +0000

Technical issues

https://gardenlightinglondon.co.uk/useful-information/mains-versus-low-voltage-for-garden-lighting/

Reels

On french extension wheels have a disconnection button.

Standards

BS 7909:2011 British temporary electrical system

Code of practice for temporary electrical systems for entertainment and related purposes

Size of event

Events are divided into different sizes

IP 67 and IP44

https://www.tcad.co.uk/ip44-ip67-plugs-shall-choose/

Toolstation sells IP67 connectors

ur plugs are made by Lewden but other manufacturers include Gewiss and ABB.

There are also Chinese Manufacturers:

H07 RN-F and Arctic Cable

“USE OF ARCTIC CABLE - Ref BS7909 2011 Code of Practice for Temporary Electrical Systems for Entertainment and related Purposes Arctic Blue able can often be seen outdoors at events. This is not recommended in BS7909 2011, despite its widespread use. BS7909 2011 recommends the use of HO7 RN-F cables for outside use”

RGB Floodlights

Sat, 24 Nov 2018 00:00:00 +0000

Aim to cover RGB flood lights that can be sourced in the both the UK and France, should have long term support by been made by named manufacturers.

IP Ratings

DSMT have a useful description.

IP 6x is dust tight which is the minimium for outside use

Rating	Meaning
IP 65	6.3mm jets from any direction
IP 66	12.5mm jets from any direction
IP 66	1M submersion
IP 68	beyond 1M eg Hermetically sealed

Table of Lamps

Lamp	Amazon UK	Amazon Fr	Manufacturer	Watt	IP Rating	comment
Loftek 50W	Loftec50WUK £33	[Loftec50WFr] N/A	Loftek	50W	IP66	RGBW, with TV type control
Loftek 30W		[Loftec50WFr] 23Eur	Loftek	50W	IP66	RGBW, with TV type control
Ustellar 60W	[Ustellar60UK] £36(min 2)					IR credit card Controller
Ilux 10W	Ilux10UK £19					Mesh Bluetooth and app

Ustellar 60W RGB Flood lights

The unit looks quite good. The cooling fins at the back look very thin. In use the lamp was not getting noticeably warm. I took off the cover of the Unit by unscrewing 8 scres and you can see the insides:
USTellarRGB60W first dissasembly

Companies House Micro Entity accounts

Sat, 27 Oct 2018 00:00:00 +0000

This is about the process of using the companies house web site to enter accounts. In Xero there are templates which produce the information you need.

Accounts prepared to FRS 105.

Directors loans

The following is on the assumption that the directors loans are below 7,500Euro and so disclosure is not required in the notes. FRS 105 (March 2018) 6B.20 Note 11

Page 1 Balance Sheet

There is a PDF of Page 1.

Calibration of Ormerod

Sat, 23 Jun 2018 00:00:00 +0000

The aim is to calibrate the Ormerod so that I can accurately print meshing gears for my BluRay Robot. My current version doesn’t work well enough.

I also want to explore using the stepper motor limit currents to allow probing of the extruder. I am assuming that the limiting current is proportional to the force.

Good Prints

Requires both Slic3r settings and RepRap firmware settings to agree as well as be calibration to actual hardware and to the filament.

Xero Accounting Tips on Errors

Wed, 18 Apr 2018 00:00:00 +0000

Bank reconciliation

Old year unreconciled account.

Dealing with drummonds.net a couple of problems became apparent:

a duplicate unreconciled bank transaction had got into the final accounts
This helped but was not the only reason the bank reonciliation was close but not accurate.

Non material difference

The difference was small < £100 so an opening year correction was done. In addition the prior year duplicate was reconciled and then corrected on the first day of the current year.

Company Cars

Wed, 04 Apr 2018 00:00:00 +0000

Company cards are probably a bad idea, ie they are a more expensive way of getting a benefit than direct ownership.

Disposal of cars

When the car is disposed of, if the company is VAT regsitered.

Xero Accounting Tips

Sat, 10 Mar 2018 00:00:00 +0000

Directors loan

Directors loan Pay money in.

The standard directors loan account is NC 835. This can be marked so that you can Enable payments to this account

When you pay money into the company for working capital.

From other source

Set up a liability account in Xero. Code the 600 pounds to this account and the monthly payments. You then need to do a journal Debit equipment purchases and Credit the liability account. You may need to consider interest on the loan - not sure how your tax laws work, would be worth discussing with your accountant.