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Commodore PET Projects - petSD+

petSD+ - Ordering

Version 1 
(Discontinued - available by special order only)
Version 2 



February 1st 2021

* * * A N N O U N C E M E N T * * *

Unfortunately, my time manufacturing petSD+ has come to an end. Outstanding orders will be fulfilled, but I won't be taking any more orders from today. There are a number of reasons for this :
1 Ongoing issues with either my assembly of the hardware or the undiagnosed firmware issue that I have mentioned previously means that I am spending a disproportionate amount of time testing petSD+ to find MCUs that work reliably and quite frankly, I have had enough of the frustration and wasted time.
2 Brexit ! The fall out from this has made ordering parts that I have previously sourced from outside the UK a real problem. Things may get better over the months and years to come, but in the short term, it has caused supply issues and will lead to increased cost - both of the parts that I use and for end users in Europe who will now likely have to pay local VAT on top of my previously VAT free prices.
3 There are alternatives available. When I started this journey, it was driven by my need for an SD card solution for my own PET. The manufacturer of Nils' previous model (petSD) had stopped making them due to illness and making one for myself was the only option. I worked with Nils on development of the upgraded petSD+ and began to offer them for sale, mainly to help folks who couldn't, or didn't want to, make one for themselves. Since then, other SD card solutions have become available, and whilst I still believe that petSD+ is the best one out there, the availability of alternatives means that there is less call for the more expensive petSD+.
4 Other priorities. I have far too many other projects on the go, there is just not enough time available to work on them all, so petSD+ has been moving further down my list of priorities for a while and now it's time to call it a day!

So, that's it ! - It's been fun (well, mostly), but I'm done !

(I don't want to leave previous customers high and dry, so will probably make an exception
for previous customers who want to replace an existing petSD+, or to add another for an
additional PET they might obtain, to maintain a consistent hardware setup.)

June 26th 2020

* * * Issues with NODISKEMU and REL Files * * *

Quoting from the NODISKEMU firmware README file . . .

"Partial REL file support is implemented. It should work fine for existing files, but creating new files and/or adding records to existing files may fail. REL files in disk images are not supported yet, only as files on a FAT medium." 
Note: this restriction also exists in other devices based on SD2IEC firmware

August 29th 2019


I am convinced that there is a bug in the NODISKEMU firmware that prevents proper initialisation of petSD+ at start-up with SOME MCUs. I think that I have eliminated all other possibilities and with the status of NODISKEMU now being unmaintained, this issue is unlikely to be fixed.

If you purchase a petSD+ Version 2, there is a high probability that the device will require a reset on power on before it starts up properly.
(See here for details)

If you cannot live with this minor, but nevertheless undesirable, behavior, then please think twice before ordering. Unfortunately, I am unable to fix this issue and cannot accept returns for devices that exhibit this behavior.

August 24th 2019


The petSD+ firmware (NODISKEMU) is now unmaintained

Nils is no longer developing or supporting petSD+ / NODISKEMU
Follow the link above for details and the implication of this development
5th June 2019

Luis Fernando Salazar, has created a really neat 3D printed case for petSD+ Version 2. For full details about the case and how to contact Luis to order one see this page

13th May 2019

The case options available for Version 1.x of petSD+ are not suitable for Version2.x so have been removed from the Ordering Page to avoid confusion.

For any petSD+ Version 1 owners who may be interested, the information is archived on the Old News page

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

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

For earlier "news" / errata, see the "petSD+ News" page

NB : I am not a dealer or trader, this stuff is just a hobby for me. There isn't a fancy web shop or on-line ordering facility - given the tiny quantity of items that I sell, there's no justification for that, "orders" or enquiries should be sent by e-mail.

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.  3
  • 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 Royal Mail's "Tracked and Insured" service (which is not cheap), 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, 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.

Price Increase Effective 01 February 2019 Changed prices shown in Blue

Base Prices 1

  Kit Prices Pre-Assembled & Tested
$ 1 Euro 1
$ 1 Euro 1
All features/external
65 78 68
80 105 91
No LCD Display
-5 -7 -6
-8 -12 -10
Internal (no LCD, no IEC)
-9 -15 -13
-12 -20 -16
Power Cable2
+5 +6 +5
+6 +7 +6
+7 +7 +6
+7 +7 +6
Deluxe LCD Display    
+12 +15 +13
+12 +15 +13

Examples :

If you would like a kit without the LCD, the price would be 65 - 5 = 60

If you would like an assembled & tested unit without the LCD, the price would be 80 - 8 = 72


Notes :

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

2 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


3 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+.


Update : 22/07/2019


I have been advised that that money making machine that is PayPal charges the sender, even when making "Gift" payments if they user other currencies than their local one, at least, it seems to charge for Euros to Pounds. I'm not sure if it is a percentage of the transaction, or a fixed fee, but you may find that is costs in the region of 3 Euros to send me the payment as a gift.



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.


Units for internal mounting are fitted with a 26 way IDC socket for user connection to the PET, no cable is provided as standard. The user will normally use a 26 way IDC cable to connect to the 2 x 12 pin internal IEEE-488 header available on most PETs. The header block is usually not fitted and will require soldering by the user to allow an IDC cable to be connected. If ordering a petSD+ for internal mounting, please ensure that you know how you will connect it to the PET before purchase.


Last updated : 30th January 2018


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.

Version 1 of petSD+ had a contrast adjustment pot, but the display brightness level was fixed by the value of resistor R2. The fixed value that I used gave an acceptable level of brightness for the majority of users, but could easily be replaced with a different value by the end user.

Version 2 of petSD+ has fully adjustable contrast and brightness.

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 expected to be popular, green text on a yellow/green background. However, not many people opted for this colour so I am not stocking them, though they are available for order if you want one.

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.

   "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" or "Yellow on Black"
Additional Cost 12
This is the "Green on Black" FSTN display that I was 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.
18/01/2018 I have been unable to source further supplies of the "Deluxe" FSTN LCD Displays, but have been able to source higher quality VATN displays which are around twice the price of the FSTN ones. I need to pass on some (but not all) of the additional price to buyers, therefore, the enhanced screen option will now be 12 (previously 7).

(If anyone can point me to alternative sources of the FSTN displays I would appreciate it. If I can get the displays cheaper, then I will be able to reduce the additional charge for the enhanced display option.)

Note: the new displays use VATN (Vertically Aligned Twisted Nematic) technology, rather than the FSTN technology in the previous ones. In VATN displays, the liquid crystals align vertically when the voltage is zero, this creates a truly black background to the display. When voltage is applied, the liquid crystals shift to a tilted position allowing light to pass through and create a gray-scale display depending on the amount of tilt generated by the electric field.

VATN displays have a super black background, there is no "bleed through" of the backlight that could be seen on the FSTN displays, they have a Super high contrast ratio and the text is noticeably sharper.

This obviously comes at a cost, but if you do want to splash out on one of these screens, you won't be disappointed !
The Green on Black VATN display (still with the protective film over the display area)
This photo is an attempt to show the difference between the Green on Black FSTN (upper) and VATN (lower) displays. The photo has not been "photo-shopped" - merely cropped. Click on the image to see the full size original photo, where the displays were photographed side by side on two simultaneously powered petSD+ Version 1 PCBs)

The contrast on the FSTN display is turned up to maximum brightness level before the backlight bleed through becomes to high. The VATN display is adjusted to the optimum level (to my eyes anyway). Hopefully, you can see how much better the VATN display is.
The Green on Black displays proved to be the most popular "deluxe" option, outselling the Amber on Black by about 10:1. Given the low volume of sales of the Amber displays, I will not be restocking these unless specifically requested to provide them (which will result in an 10-12 week delay before I could obtain them).

Available on back-order only


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
1  1.20 1.4
12 14 12
4 6 5
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 11.50, or 13 + 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, 17.00 + 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+ Version 1 with a Commodore 64

Fitted with an IEEE-488 connector and Commodore 6-pin DIN serial port connector. (Not required for petSD+ Version 2)

Limited availability, 10 + P&P
Data cable for using petSD+ Version 2 with a Commodore 64/Vic 20

This is a standard 6-pin DIN cable, as used with a C64 disk drive.

Limited availability, 7.50 + 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 - 06/06/2018 SOLD OUT




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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