Search found 39 matches

by shanevi
Wed Aug 24, 2016 9:51 pm
Forum: Off Topic
Topic: Jaycar Bunbury looking to hire a casual
Replies: 2
Views: 10553

Jaycar Bunbury looking to hire a casual

Hi all. Jaycar in Blair St Bunbury are looking to hire a casual sales assistant. Hours will likely be during the middle of the day and possibly weekends, though may be at other rostered times as well. An electronics knowledge and/or background is highly preferable. Please send or drop of resumes to ...
by shanevi
Sat Aug 20, 2016 11:39 pm
Forum: Projects
Topic: Powerbank
Replies: 4
Views: 6344

Re: Powerbank

Awesome :)
Did a similar setup with a 12AH SLA to power telescope remotely last year :)
by shanevi
Thu Jan 08, 2015 10:25 pm
Forum: General Discussion
Topic: New phpBB I see :)
Replies: 3
Views: 4936

Re: New phpBB I see :)

It's been awhile since you've been on ;)
:D
by shanevi
Sat Dec 20, 2014 10:55 pm
Forum: Product Reviews
Topic: EveryCircuit - Android App
Replies: 1
Views: 6245

EveryCircuit - Android App

http://everycircuit.com/

I've been using this on my Android phone for about a month now. Brilliant bit of software. Schematic design and simulation with Virtual CRO, Voltmeter, Ampmeter etc...
I use it to draw up quick simulations for customers for more in-depth discussion of their own circuit ideas.
by shanevi
Tue Nov 25, 2014 9:55 pm
Forum: Projects
Topic: My Z80 Computer build
Replies: 14
Views: 13405

Re: My Z80 Computer build

Tonight I did final test on power and for shorts. ATMEga328 was programmed with my program, plugged into the z80 main board and powered up. The LED flashing is just a late addition to get a feedback from uController. Video is located here showing the power up and cycle from Reset hold to Regular ope...
by shanevi
Tue Nov 25, 2014 12:16 am
Forum: Projects
Topic: My Z80 Computer build
Replies: 14
Views: 13405

Re: My Z80 Computer build

Thanks for that I got my needed 7432 once Jaycar opened Though you should probably built a TTL gate computer out of all you gates would make an awesome project I have written a quick test for the LED monitor, 2MHz Clock and Reset Hold signal. The code is a bit dirty but it is only important, for now...
by shanevi
Sun Nov 23, 2014 6:59 pm
Forum: Projects
Topic: My Z80 Computer build
Replies: 14
Views: 13405

Re: My Z80 Computer build

Moving along not as fast as I had hoped this weekend I did manage to wire up the missing links and pieces, terminating most tracks where they need to be and just checking random points. uController has still a couple missing routes. I have also added, modifyed schematic on the fly, 3x 4k7 pullup res...
by shanevi
Wed Nov 19, 2014 11:54 pm
Forum: Projects
Topic: My Z80 Computer build
Replies: 14
Views: 13405

Re: My Z80 Computer build

Due to the latency on the ATMega328 (which I had a feeling it would be in simulation) I have reverted back to a 74hc32 as the IO and Mem decoder, However I have kept the ATMega in circuit as a very reliable adjustable clock source and boot reset. I have also provisioned for the next expansion (IO), ...
by shanevi
Tue Nov 18, 2014 11:07 pm
Forum: Projects
Topic: My Z80 Computer build
Replies: 14
Views: 13405

Re: My Z80 Computer build

Arduino works great as a 2MHz clock generator. A good clean 1.9998 MHz clock output from pin 5 with a 49.9% duty cycle. Clean enough Though I am seriously contemplating going straight to using my recently acquired OR gates to do the decoding for memory and IO once again (the uC runs as a decoder up ...
by shanevi
Fri Nov 14, 2014 8:19 pm
Forum: Projects
Topic: My Z80 Computer build
Replies: 14
Views: 13405

Re: My Z80 Computer build

Just had a chance to sit down in the last few days and quickly reasearch the atmega timers m <--- seems like a good starting point for what I need I have done quite easily in PIC, set a timer to run dividing clock frequency and drive other processors etc while main program runs but wasn't sure about...
by shanevi
Wed Nov 12, 2014 10:53 pm
Forum: Projects
Topic: My Z80 Computer build
Replies: 14
Views: 13405

Re: My Z80 Computer build

Hi BeJay, I did have a problem in the beginning, reports of oscillation at 20-32MHz from my buspirate. definitely not right. One of the caps on the oscillator wasn't making a good connection. I know from experience, that these oscillator setups that is that the caps are a necessity. Apparently it wi...
by shanevi
Wed Nov 12, 2014 3:58 pm
Forum: Projects
Topic: My Z80 Computer build
Replies: 14
Views: 13405

Re: My Z80 Computer build

A mid-project redesign of the main board Z80 System.jpg I have gone with using a ATMega running at 16MHz to drive the logic for Memory and IO decoding. A short programming running in loop on uController checks inputs and outputs corresponding outputs accordingly. Using this uC allows for possibility...
by shanevi
Sun Nov 09, 2014 10:37 pm
Forum: Projects
Topic: My Z80 Computer build
Replies: 14
Views: 13405

Re: My Z80 Computer build

The wiring for address lines from CPU to EEPROM to SRAM are all done top and bottom. Have yet to terminate tracks undersideaddressanddata.jpg Top side of board showing wired data lines. I have sitting on top of the board my EPM570 CPLD... I still haven't aquired a Quad OR TTL, nor sat down and desig...
by shanevi
Fri Nov 07, 2014 6:16 pm
Forum: Projects
Topic: My Z80 Computer build
Replies: 14
Views: 13405

Re: My Z80 Computer build

Z80Data.jpg And why are the Z80 Data lines like they are again? :/ lol Z80 Template.jpg One thing I have learnt when breadboarding digital electronics is to create little templates (in reverse) for the underside of the board. This allows easier wiring to various chips on the board. This particular ...
by shanevi
Thu Nov 06, 2014 4:45 pm
Forum: Projects
Topic: My Z80 Computer build
Replies: 14
Views: 13405

Re: My Z80 Computer build (32kB ROM/32kB ROM - 2 MHz)

A few hours later I quickly put together a circuit to test one of the near 25 year old CPUs I have in possession. Tie all Data pins to ground, creating a permanent $00 each time the CPU reads the data line. A few LEDs on the LSB off Address lines to monitor and an Arduino to provide the 2Hz clock pu...
by shanevi
Thu Nov 06, 2014 11:47 am
Forum: Projects
Topic: My Z80 Computer build
Replies: 14
Views: 13405

My Z80 Computer build

And yet another Z80 computer build. This time I decided to go old skool This is the second time I've built a Z80 system. The first one was back about 20 years ago. Long gone during many moves. As with most projects I start stages with breadboarding and move over to my lovely stripboards Computers ar...
by shanevi
Sat Nov 01, 2014 1:05 pm
Forum: Arduino
Topic: Using my Arduino as a Serial TTL - USB convertor
Replies: 2
Views: 5766

Re: Using my Arduino as a Serial TTL - USB convertor

I think ou can do same with Uno etc...
in that case should be able to either remove the DIP IC, or do the same.. Tie reset to Ground.

Tight budget always allows one to think further outside the box ;)
by shanevi
Fri Oct 31, 2014 10:27 am
Forum: Arduino
Topic: Using my Arduino as a Serial TTL - USB convertor
Replies: 2
Views: 5766

Using my Arduino as a Serial TTL - USB convertor

Probably already known by all but I thought it was quite a neat dirty hack.... I didn't have a spare Serial to USB convertor on hand for a recent project. So decided to try my arduino mega (Should be able to do with others also) connect wire from Reset to Ground. This will hold all Atmel pins in hig...
by shanevi
Sun Oct 26, 2014 1:00 pm
Forum: General Discussion
Topic: Jaycar coming to Bunbury :)
Replies: 2
Views: 3665

Re: Jaycar coming to Bunbury :)

Definitely more resistors than DSE though :D
by shanevi
Thu Oct 23, 2014 12:10 pm
Forum: General Discussion
Topic: Jaycar coming to Bunbury :)
Replies: 2
Views: 3665

Jaycar coming to Bunbury :)

I'm excited. Jaycar coming to Bunbury. :)

http://jaycar.com.au/news.asp?ID=1532