Duncan Maidens
Hi. I am one of the team at Raspberry Pi with responsibility for content across A level and GCSE materials for Computer Science.
My main area of specialisation is computer networking and security
Location Shropshire UK
Activity
-
Duncan Maidens replied to Jiun T
Hi Juin . We have included a new section in the topic to suggest ways to share a file (See above). Thanks for asking this and helping us improve the courses. :-)
-
Duncan Maidens replied to Jiun T
Excellent. Can you add to it to feedback as to how many tries it took the user when they get it correct?
-
Duncan Maidens replied to Jiun T
Excellent
-
Excellent. - Well done. Not quite sure on the logic of needing sufficient funds in both the bank account and (savings or cheque ) account but that is a minor detail.
-
Duncan Maidens replied to Jiun T
Ah. Yes now I see what you are saying. Yes in this case we can simplify the circuit above by feeding A & B into an AND gate and then inverting the output. (Thus doing away with the second AND gate).
Often the logic comes about from the way we think about the conditions. We then draw it out and look for ways to simplify it. We also do this using Boolean logic. -
Duncan Maidens made a comment
All. Welcome to week two. If you have not yet added any comments, don't be shy. Share your thoughts, observation and/or questions here at the end of each step. See what your fellow learners post and engage with them.
It ramps up a bit in this week so stick with it and you should experience the joy of writing some code.
If any of it is not making sense,... -
Pastebin should let you display the text with the correct indentation in file from the python editor. Just copy and paste it into 'Pastebin' then go to share the link via twitter. Just copy the link from the post before you delete it . (Unless you want to tweet about it :-) )
-
I recall playing with this some time ago. Yes, great idea to engage kids with. I found this tutorial on it here.
https://minecraft.wonderhowto.com/news/redstone-logic-gates-mastering-fundamental-building-blocks-for-creating-game-machines-0135063/ -
Duncan Maidens replied to Jiun T
I admire your perseverance with a text editor :-) Looks good.
-
Duncan Maidens replied to Jiun T
Share your thoughts here because I can't see how. A NOT gate has only one input where as an AND gate has at least 2.
-
Welcome. Yes, i too love those escape room puzzles. Lots of ideas here in logic.
-
Did you convert the binary numbers to decimal as well (mentioned half way through the article)?
-
What about 255 and 256 ? Can you see how, for numbers like; 3, 7, 15, 31, 63, 127 and 255 we can easily convert to binary without adding up the value of each individual digit ?
-
Duncan Maidens replied to David Webb
If you look at the diagram and work through it you will see you can put as many cross-over switches together as you want to create a 4,5,.... way switching system for really tall buildings.
The fun them comes in swapping them to the pneumatic time switches that you press to switch on the light, and they pop out (after a delay) to switch the lights off. ... -
Duncan Maidens replied to David Webb
@DavidWebb Hi. One of the switches will be a special switch for just such purposes called a cross-over switch. See https://www.lightwiring.co.uk/tag/3-way-lighting-circuit/
-
Duncan Maidens replied to Jiun T
If it has just two stops then YES it could be used to think on the logic states. The top position could be a logic 1 and the lower position a logic 0. We could then say we need to send the lift up when 'the call button on the top floor is pressed' AND 'the lift is on the bottom floor'
We could all say. 'when the call button has been pressed' AND ' the lift... -
If all the jargon around Python is not making any sense, don't panic.
Python is a computer programming language like many others you may have heard of (c, C++, c#, java, basic, pascal, Fortran, to name but a few.). On a desktop computer, we need a program that will allow us to write our programs (a text editor) and the 'run' or 'execute' the program. ... -
The trick for combinational logic truth tables is to create a column for each of the individual outputs with the circuit (like the point labelled X). Then ignore the bigger picture and just concentrate on the one single gate for which you know the inputs and go through them step by step.
I tend to use this approach.
If it is an AND gate I am looking for... -
Duncan Maidens replied to Gifted Braimah
Yes. In reality, we can have AND gates with multiple inputs, and only when all the inputs are a logic 1, will the output be a logic 1. We can also build this by cascading together multiple 2 input AND gates.
-
Duncan Maidens replied to David Webb
2 way lights are an interesting example, but the problem is there is no 'on' or 'off' position for each switch. A more logical example would be a table lamp (with it's own switch), plugged into a switched socket. What do you need to do to get the light on?
Extending this logic you can think of a device that has battery back up as well as mains power. What... -
Duncan Maidens replied to David Webb
it is a good way to start to think of logic in terms of on and off. We often draw a digital signal as 0 and 5 volts to represent 0s and 1s, so again this view helps.
-
Sounds really interesting. I love logic problems. Made me think of this one https://www.transum.org/Maths/Puzzles/Scouts/River/
Also, have you seen the Bebras site ? -
Duncan Maidens made a comment
Hi. I am Duncan Maidens and one of the educators here at RPF. I have been teaching at a variety of places since my mid-20s, so coming up on 30 years of experience.
I hope you enjoy the course and I, or your peers will answer any questions posed in the comments sections. I will be facilitating this course over the first 3 weeks of May. -
Captcha can't stop DDoS because the website being attached will still have to deal with the user's first connection (pre captcha)
-
Duncan Maidens made a comment
Blocking the user (via their IP address) is OK for a DoS attack, but with a DDoS attack there are so many 'users' possibly coming from different sources it is much more difficult to block, whilst allowing legitimate traffic.
-
Duncan Maidens replied to Penny Cater
If you can please share details of your exercise here.
-
Generally, DNS updates don't use bots but are pushed out by DNS authorities into the hierarchy of DNS servers.
-
As a general rule only allow alphanumeric chars for database queries. Where you have passwords that may contain lots of different characters, hash them before sending which you can ensue are only alphanumeric.
Different database back ends use different commands so there may be specific combinations that you just simply do not allow. -
Duncan Maidens replied to Melissa Parker
Malware bytes has its own website so if you want it download it from there. As a general rule I would expect to pay for such protection, but there are some good free solutions out there.
-
Duncan Maidens replied to Melissa Parker
Interesting article. You can see how the early primitive version of this was store reward cards where they could build a profile of the areas you visited in a large supermarket from your purchase history.
-
Hi Phil. Are you doing this as part of the Secondary Certificate (formally the CSA Programme) ?
-
Hi Holly. Great to see this course being used so far away from the UK. Hope you make use of the other course we offer for Computer Science teachers on Future Learn and other resources on teachcomputing.org
-
Hi Rute. Alas, we don't have any Portuguese speakers as facilitators, so I will only be able to reply if you post your comments in English. However other fellow learners may respond.
Welcome -
Duncan Maidens replied to Penny Cater
If it is too good to be true it is probably not true
-
Duncan Maidens replied to tim bloore
You have brought up two things here. One is Password Generator Programs which can produce random passwords with varying characteristics such as easy to read, length, upper, lower, numbers, symbols etc. They are excellent to make a password.
Related and often combined with the generators, they are web sites called Password managers, which 'store' all your... -
@TiinaB Hi Tima Very impressed with you using your time to get up to speed on such things. The ideas of Cyber need to be taught from an early age as technology becomes more accessible to younger and younger audiences. It is so important that we start to understand the technological world in which we live from an early age so that we can be curious and...
-
@timbloore Great to have you onboard and hearing you are just interested. Who knows where this newfound knowledge may take you.
-
Welcome, Duc. Great to have participants from all over the world
-
Hi Geraldine. Are you doing this as part of the Secondary Certificate (formally the CSA Programme) ?
-
Duncan Maidens made a comment
Hi. I am Duncan Maidens, one of the educators from the Raspberry Pi Foundation(RPF).
I taught Computer Networking and Cyber Security in Higher Education for 20 years before joining RPF and now support a number of programmes here.
I will be your facilitator for the course for the next 3 weeks so will pop in and out of the discussions after each step. ...
