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Commodore PET Projects - petSD+

petSD+ - Ordering



Third party case available

Michael Schön ( has created a nice acrylic case for petSD+ and is making it available though his webshop. The case is priced at €19.00 including VAT (shipping extra). You can see a couple of photos further down this page, or on Michael's website.

The website is in German, use Google Chrome to have the page automatically translated for you, a local copy of the page, translated into English, is available here.  


Price Increase Effective 01 October 2016

As I live in the UK, petSD+ prices are quoted, and must be paid for, in UK pounds. Over the past year, exchange rates have dropped significantly, sterling having dropped from ~$1.5 USD or 1.4 Euros in October 2015 to ~ $1.3 USD or 1.1 Euros today.

Since I source most of the parts in Europe or the USA, it has become significantly more expensive for me to make petSD+, but the effective price for most customers has actually reduced from about $105/E91 to around $91/E77 today.

For the supply of petSD+ to remain viable, I need to increase the sterling prices of the kits and assembled units by 10% (less than the 15% exchange rate difference). This change will only really impact the very small minority of customers who are in the UK - international customers will not see any increase over the Dollar/Euro estimated prices on this page - they will just not get as large a currency discount as they have seen over the past year, but will still pay a little less than my estimated prices.
Changed prices shown in Blue

Please see the Order Status page to track the progress of your order or enquiry

Please see this note (below) if you intend to use Paypal from outside the UK

* * * 24/03/2016 * * *

petSD+ now supports IEC (Serial IEEE-488), i.e. Commodore 64

(requires custom cable)

 Download the latest firmware from here



A modified Editor ROM with integral DOS Wedge is really a great step forward,

every petSD+ owner should have one!

To that end, I have been investigating the possibility of being able to create one and supplying it as an option for petSD+ purchasers. Read the latest developments on this page.


Component C12 can and should be removed from ALL petSD+ devices

shipped prior to 17th October 2015.

Provided that you have some basic tools, removal of C12 is straightforward. As C12 is located behind the PREV button, if the LCD screen is fitted it should be temporarily disconnected to allow C12 to be removed - more details here.

 If you would have difficulty in doing this yourself, drop me an e-mail and we can try and work something out.


How to get a petSD+

1  Do-It-Yourself
2  Buy a kit of parts from here and assemble it yourself
3  Buy a fully built and tested petSD+ from here


petSD+ has been designed as Open Source Hardware and the NODISKEMU firmware is a fork of sd2iec, free software released under GPL Version 2. The design files for the petSD+ PCB and the firmware source and binary files are freely available from both Nils Eiler's website or from here. All of the information that you'd need to have your own PCB manufactured and enable you to assemble it are available for download.


Or, With a little help from me . . . .

If you do not want to go to the bother of getting your own PCB made, you may wish to consider one of the options for obtaining a petSD+ from me, if so, please read the bullet points below :-

  • As I am based in the UK, the payment currency will be UK pounds, I have put indicative prices in Euros and US dollars, based on typical exchange rates in June 2015 of 1.3 Euros and 1.5 Dollars to the pound. The price you pay may vary a little depending on the prevailing exchange rates when you order.
  • The most convenient option is probably Paypal but the prices shown here do not include Paypal fees, please either pay the fees yourself, or add them to the relevant price. I am happy to consider other payment options that you might like to suggest. If you are a prospective non-UK buyer considering using Paypal, please read the note below.  5
  • The prices do not include shipping - I will add shipping costs to mainland Europe and the US shortly, but in the meantime, please e-mail me with your address with postcode and I will get a price for you. Shipment will normally be using a tracked and insured service but I am happy to look at other options, provided that you bear the risks.

Buy a kit of parts from here

With help from Nils, I have put together a kit of parts required to build petSD+, the parts are available from a number of suppliers but not all from a single supplier, at least, as far as I know. You can probably source the individual parts cheaper than I have priced the kits, but you may prefer the convenience of ordering the parts in just the quantities that are needed for building a single petSD+ from a single supplier - i.e., me :-) See the Assembly page for details of building the kit.

petSD+ can be configured in a number of different ways depending on your preferences, the way that I have priced the kits is based on the premise that a "standard" petSD+ is the fully featured version which includes the following :-


Feature Description
LCD Display Used to quickly select disk images to be loaded into the virtual floppy drive and to set the Real Time Clock.
Real Time Clock Allows the current timestamp to be used when writing files to the SD card
External mounting Connected via the PET's external IEEE-488 port
Power supply (Not included) Cable from the PET's external cassette port
ISP Port Connector (Not included, not normally required if buying a kit or assembled petSD+)

Should you choose to drop features, such as the LCD or RTC, the kit price will reduce accordingly.


Buy a fully built petSD+ from here

Should you not feel confident in your own ability to assemble the kit, you may want to purchase a fully assembled and tested petSD+. It may take me a few days to build and test each one, but I will get them done as quickly as I can on an "as required" basis. Should you want to buy a fully built and tested version, please drop me an e-mail, I will start building it and give you an estimate of when it will be completed. Only after it is built will I ask you to pay.

The majority of orders to date have been for pre-assembled units, although I am getting better/faster, I did underestimate the time that it would take me to build and test petSD+. Therefore, I have decided to make a small increase in the price for pre-assembled units, the revised prices are shown below.

Given the time and effort involved in building them, I think the price is very fair, but you are welcome to comment if you disagree.

Base Prices 1

  Kit Prices Pre-Assembled & Tested
£ $ 2 Euro 2
£ $ 2 Euro 2
All features/external
55 75 68
77 105 91
No LCD Display
-5 -7 -6
-8 -12 -10
No Real Time Clock
-4 -6 -5
-5 -7 -6
Internal (no LCD, no RTC)
-10 -15 -13
-14 -20 -18
Power Cable3
+5 +6 +5
+6 +7 +6
+6 +7 +6
+6 +7 +6
Deluxe LCD Display    
+7 +12 +10
+7 +12 +10

Examples :

If you would like a kit without the real time clock, the price would be £55 - £4 = £51

If you would like an assembled & tested unit without the LCD, the price would be £77 - £8 = £69


Notes :

1 Prices subject to change as the design develops and/or I get more certainty around my costs

2 US Dollar and Euro prices are estimates, please pay in UK pounds

3 An improved power cable is now available, but has slightly increased the price of the cable option.

4 petSD+ would normally get power from the PET cassette port via a short cable that connects to the power input of petSD+. If you prefer, I can supply a "wall wart" AC/DC converter instead, for the additional cost shown


5 Non-UK purchases using Paypal.

Until I reviewed my Paypal account after the first couple of international sales, I did not realise that the Paypal money making machine also screws more money out of me if I accept Paypal for non-UK orders, even if paid in UK pounds. This scam is called a "Cross Border Fee" - it certainly made me very cross !


The additional cost increases the Paypal charges from 3.4% +£0.20, to anywhere between 3.8% +£0.20 and 5.2% +£0.20, depending on the country. This increased cost will need to be added to the total price if using Paypal to place an order for petSD+.


It is possible to avoid having to pay these, or indeed any, Paypal fees if you are happy to send the payment as a "Gift". You may wish to consider that option, assuming that you are happy to trust me :-)


To help instill that trust, I thought that it would be helpful to add a "Feedback" page where people can enter their experience of the ordering process and/or feedback their experiences with petSD+.


NB : For the avoidance of doubt, petSD+ does not connect directly to a PET computer, the "standard" build of petSD+ is fitted with an IEEE-488 connector like those found on PET disk drives. Most PET and CBM computers use a cheap PCB edge connector to provide IEEE-488 connectivity, to connect petSD+ or a Commodore disk drive, you need to use a Commodore IEEE-488 disk drive cable (hard to find) or a PET to IEEE-488 adapter along with a standard IEEE-488 cable.


Last updated : 27th September 2016


Too expensive? - Please read this note





LCD Colour Options

The LCD displays that I am using are available in a couple of different colours, if you don't have a preference, I will fit a display that I either have available, or can get relatively quickly. If you want to choose a particular colour, or specifically don't want any of them, please let me know and if there is going to be any significant delay in getting the colour of your choice, I will let you know.

The white on blue comes out best in the images below, but that is more to do with the performance of my iPhone's camera - it does not seem to do as much justice to the other colour displays. I think that they are better than the photos might suggest.

nb: The current version of petSD+ has a contrast adjustment pot, but the display brightness level is fixed by the value of resistor R2. The fixed value supplied in my kits or fitted to pre-assembled units, should give an acceptable level of brightness for the majority of users, however, being located on the top of the LCD, the resistor can easily be replaced with a different value by the end user - subject to the electrical specification of the display being respected.

For more detail, see the LCD description on my petSD+ hardware page.


To Order :
Specify "White on Blue" or "Green on Yellow"
Standard Colours
I know that Nils wasn't keen on using a blue display, but I quite like this one. Click on the photo to see the full size image, the full size photo has not been touched up - other than being cropped.

The photo is pretty much as it came off my iPhone, taken with no flash to show up the display better - at the expense of the LCD PCB appearing overly dark. As you can see, the display is pretty nice, well, I think so.

This is the other colour option that I expect to be popular, green text on a yellow/green background.

The White on Blue and Green on Yellow LCDs seem to be the most cost effective ones and are the ones that I plan to have available by default.
Reflective Display Option

To cater for the environmentalists out there, who may be looking to save energy, I have a limited number of reflective LCD displays available. (There is absolutely no truth in any rumors that these were bought in error!)

No longer available

   "Deluxe" Colour Options  

This photo is of the petSD+ that Nils built for me, as you can see, it has a green on "black" display and is quite pleasing on the eye. It is also quite similar to the PET's own display colours.

Because they are harder for me to get, I had not planned on making this display available, but, by popular demand (OK, I mean that I have had two requests), I am able to do so, but they are slightly more expensive than the ones above, so there will be a small extra charge for this option.
To Order :
Specify "Green on Black", "Amber on Black" or "Pale Blue"
Additional Cost £7
This is the "Green on Black" display that I am able to supply.

It is not apparent from the photo, but the colour is very close to the display that Nils sent me, shown above. In fact, I think that I will be using the same supplier that Nils used.
I can also supply it in what was described as "Yellow on Black", the photo makes it look very yellow, but the colour is actually much closer to Amber on black, very much like the colours of the IBM Portable screen.

For comparison, this is the seller's photo showing the display colour, this is a much closer match to what the display looks like in practice.
I also bought one advertised as "Black letters, White background". Again, the photo doesn't give a very good representation of the colours, but as it suggests, the display would be more accurately described as "Dark Blue on Pale Blue" although in reality, the blue is not as pronounced as the photo suggests

It is definitely not Black on White, but quite nice all the same.

For comparison, this is the seller's photo showing the display colour, it does appear closer to black and white, but, as I know now, that is down to the quality of the photo, rather than the actual colour.

No longer available


Case, including PCB supports, bolts, etc. (Ordered on request)  
PCB M3 spacer bolts, distance sleeves, pan head screws - set of 4  
Retro Innovations IEEE cable adapter (very limited "stock")  
MicroSD to SD card adapter (new) + 128MB MicroSD card (used)  
£ $ 1 Euro 2
5 7 6
1  1.20 1.4
10.5 14 12
4 6 5
We had planned to offer a case option for petSD+, based on the same style as used for the original petSD. This is my "Photo shopped" mock-up of how petSD+ might look with the LCD display fitted to the case that Nils had in mind ( stock no. SD 10 GR HALB/SD 20 GR HALB).

Unfortunately though, although the proposed case for petSD+ is workable, Nils found that the installation was very tricky and time consuming, so it was not really practical to offer the case as an option.

For units with the display, not having a case is not really a problem as the PCB supports raise the bottom of petSD+ off the desk and make it level. For units without the display, you might like to think how the petSD+ will sit on your desk, particularly as the battery holder is on the underside of the PCB.

Nils did buy a few cases with a view to making them available as standard, now that we are not going to do that, I have a few spares. The bottom half of the case could be used without modification to hold the PCB and if you wanted to spend some time on it, you could add the holes required in the top half of the case to completely enclose petSD+ if you wanted to.

I can offer the cases, including the PCB supports (shown below), for £5 ($7, Euro 6), available in grey (shown) or black.

The cases are now sold out but can be ordered on request.

Alternatively, if you just need a set of the PCB supports, including 4 x M3 spacer bolts, 4 x M3 distance sleeves and 4 x Philips pan-head screws, I can supply a set for £1.50.
Rainer Fritz has mounted his petSD+ in a very similar case, available from Conrad Electronics as part number 521035 - 62. It looks to be the same case, split 50:50, rather than the 1/3 : 2/3 of the cases that I have available.

Photo courtesy of Rainer Fritz
Rainer's petSD+, showing the rear of the case with the IEEE-488 connector and power input lead.

Photo courtesy of Rainer Fritz
And a view from the front, showing the controls, indicators and SD card slot

Photo courtesy of Rainer Fritz
Third Party Case Option - For Information Only

Juergen Krieg has let me know that he has sourced a nice acrylic case  for his petSD+ from Michael Schön (

Michael is now making the case available though his webshop. The case is priced at €19.00 including VAT (shipping extra). It's more expensive than the cases that I am able to offer, but is custom made for petSD+, so fitting it is a much easier process than modifying one of my off-the-shelf cases.

Photos courtesy of Juergen Krieg

To purchase the acrylic case, please contact Michael through his webshop
If you don't have a Commodore edge connector to IEEE-488 cable, you might like to get one of these IEEE cable adapters from Retro Innovations in the US ($10). When I bought mine, the shipping cost was another $10.

I have just bought another batch but I had to pay VAT, Royal Mail's VAT collection charge and shipping, which means that I have to put the price up. I can supply one with petSD+ for £10.50, or £12 + P&P on its own. For buyers in Europe, this is probably cheaper than you could buy direct.

Image courtesy of RETRO Innovations

CAUTION : Take care when connecting the adapter to your PET, from Retro Innovations the web page :

The IEEE connector should be "under" the PCB when installed (the PCB lettering should be "up"). 
IEEE-488 Cable, 1.0m long, new, with metal connectors.

Limited availability, £15 + P&P

: This is a standard IEEE-488/GPIB cable with 24-pin male & female connectors at each end for "daisy-chaining" multiple devices. Most PET users will also need one of the cable adapters shown above to attach the cable to the PET edge connector. (I have a very limited stock of original commodore cables that don't need the adapter - see below)
I guess that most potential petSD+ users will already have access to a range of PET software or will be able to download it from the web.

For anyone who doesn't have software available, I am considering making an SD card available with some (to be determined) software on it. I have picked up a few second hand (ex.Nokia) 128MB microSD cards and could supply one with an adapter for £4 - let me know if you are interested. (The micro cards are now sold out, but I now have some full size ones)

I have picked up a few standard size 128MB SD Cards and I can supply the same software on these cards for £5.
Data cable for using petSD+ with a Commodore 64

Fitted with an IEEE-488 connector and Commodore 6-pin DIN serial port connector.

Limited availability, £10 + P&P
Original Commodore PET IEEE-488 Data Cable - no adapter required

I have just picked up a few "NOS" original PET-IEEE cables, the metalwork is slightly tarnished with age, but they work perfectly.

Limited availability, email me for a price, or make me an offer !




Status : 01 July May 2016

The current version of the firmware for petSD+ now fully supports disk read/write functions and the Real Time Clock, in addition, the LCD can now be used to change the Device Address, change directory and load disk images.

The boot loader is able to re-flash the MCU from a binary file copied to the SD card, no additional user programming of petSD+ is required. The firmware release are compatible with all versions of petSD/perSD+.

A copy of the latest firmware binary file, is available from an auto-generated nightlies page on Nils' site.

A modified version 2 PCB is currently being designed by Nils, but this may take a little while to make it into production. Version 2 is likely to feature enhanced control of the LCD brightness and contrast using PWM and a few other minor improvements.

In the meantime, a slightly modified version "1.2" board is now on order, it corrects a number of minor issues with earlier versions of the board (1.0, 1.1, 1.1a), including :-

  •  the MISO connection issue described in Nils' errata link on his web page. (This issue is only relevant to petSD+ boards that have the ISP port connector fitted which will not be needed by most users anyway).

  • removal of the redundant capacitor, C12



Indicative shipping costs - subject to confirmation

  Tracked & Signed for Untracked (at your risk)
Kit - no LCD £3.90 £9.50 £10.50 n/a £4.50 £5.50
Kit - including LCD £4.90 £11.50 £13.70 tbc tbc tbc
Assembled - no LCD tbc £10.70 tbc tbc tbc tbc
Assembled - including LCD tbc £12.60 £14.50 tbc tbc tbc
Prices are based on using the UK postal service, Royal Mail. Packages are transported to the destination country and handed off to the local postal service for delivery. I am happy to use other shipping options if you prefer.


Should you wish to take up any of these options, or have any questions, please

send me an e-mail

See the status of your order



A word about the price . . . . .

The price of a fully assembled petSD+ is now a little more than I had anticipated and probably doesn't really qualify as "low-cost" anymore. I wanted to say a few words about the price and, while not necessarily justifying it, at least give some insight into how the price has been set.

At the outset, I would like to encourage you to bear in mind the difference between cost and value.

I think that the product closest to petSD+ in terms of form and features is the HxC Rev. C Floppy Emulator from Lotharek. Although HxC although does not emulate PET/CBM floppy drives, it has the same Prev/Next/Select buttons and LCD screen (although half the size) functionality as petSD+. The current (as of 24/08/15) price for a Rev C. HxC, excluding shipping, is just under 70 Euros, i.e., about 20 Euros less than petSD+.

HxC is more flexible than petSD+ in that it can be used with a wide range of Shugart compatible systems, including vintage home micros, IBM compatibles and industrial systems. This brings economies of scale to the HxC product; bulk component purchases will be cheaper and the larger volume of production allows manufacture to be outsourced to an automated manufacturing facility. For petSD+, I have to purchase the components in small quantities, build the devices by hand and absorb the cost of any, hopefully few, failures during construction.

The time that it takes me to build and test each petSD+ is not insignificant, if I paid someone to do it at the price that I charge, I would be in breach of the UK's minimum wage regulations :-)  The time taken is obviously a function of my less than impressive soldering capabilities, you could probably build one faster, should you choose to, but the price is based on the time that it takes me.

 Kit Pricing

You can probably source the individual parts cheaper than I have priced the kits, but you may prefer the convenience of ordering the parts in just the quantities that are needed for building a single petSD+ from a single supplier. I do add a small mark-up to the cost of the parts, this is intended to cover the time required to order the parts, apportion the costs for price and delivery to individual kits and the time taken for me to assemble the kits. If you have received a kit, I hope you will agree that the time spent in preparing it was reflected in the package that you received.

Your thoughts ?

I would be interested in your thoughts on the subject, you can either send me an e-mail , or leave a comment here




Definitions from The Free Dictionary
Cost : An amount paid or required in payment for a purchase; a price.
Value : An amount, as of goods, services, or money, considered to be a fair and suitable equivalent for something else; a fair price or return.


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