New batch of Datanetics Rev B keyboard set

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New batch of Datanetics Rev B keyboard set

Just assembled a few more keyboard sets over the weekend. You can get it from the ebay link below or PM me for $150 plus shipping. Thanks for your interest.

 

https://www.ebay.com/itm/265914613027

 

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Highly recommended! 

Highly recommended!

 

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Has anyone used this on a

Has anyone used this on a Briel Replica-1 plus? There is an ascii keyboard socket present with a jumper to enable it.

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Hi Mike, I might be

Hi Mike, I might be interested. How much is the shipping to The Netherlands? And do you might have an additional ACI pcb for me too?

 

Thanks, Bobby

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skate323k137 wrote:Has anyone
skate323k137 wrote:

Has anyone used this on a Briel Replica-1 plus? There is an ascii keyboard socket present with a jumper to enable it.

I am very interested to know that too.. If Replica-1 can work with Apple II plus keyboard, I believe most likely it works with the Datanetics keyboard as well.

 

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NewtonMike wrote:skate323k137
NewtonMike wrote:
skate323k137 wrote:

Has anyone used this on a Briel Replica-1 plus? There is an ascii keyboard socket present with a jumper to enable it.

I am very interested to know that too.. If Replica-1 can work with Apple II plus keyboard, I believe most likely it works with the Datanetics keyboard as well.

 

Glad to hear you are also curious. I have a II+ (two, actually) which I could theoretically borrow a keyboard from for testing, but in looking into this I found this information:

The ASCII keyboard port has been retained but for Apple II keyboards, a -12V supply or a Super Encoder board enhanced Apple II keyboard is required.

 

 None of my Briel's have a -12 hooked to the (optional) -12v input, as Uncle Bernie's revised ACI did not need anything beyond the 5V present. But I would probably sooner find a -12v supply than replace an entire encoder in one of my keyboards if those are my only options to test this out. 

 

Sorry if this is a derail of your thread, I could start a thread on this topic in particular if needed. But I think it would be awesome for Replica-1 owners to have your Keyboard as an option. 

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These keyboards don't need -12V

In post #6, skate323k137 wrote:

 

"The ASCII keyboard port has been retained but for Apple II keyboards, a -12V supply or a Super Encoder board enhanced Apple II keyboard is required."

 

Uncle Bernie comments:

 

This information is only true if the keyboard you want to hook to the Replica-1 actually needs the -12V supply for itself. The original Apple II keyboard (and many other 1970s keyboards) used a type MM5740 LSI keyboard encoder chip (later, AY-5-3600-931) based on PMOS technology and it so happens that this chip needs a negative supply voltage.

 

Note that the Newton keyboards DO NOT use an original vintage PMOS keyboard encoder LSI but a modern replacement based on a single chip microcontroller mounted on a PCB. These do not need (or use) the -12V supply. In fact, they would blow up if they got -12V anywhere on their pins.

 

This means that these keyboards do not need -12V. You can also put this style of replacement keyboard encoders into any Apple II keyboard and it won't need the -12V supply anymore. But you may need to reprogram the microcontroller with the software to fit the different keyboard matrix. There used to be an Ebay seller who sold this MM5740 replacement pre-programmed to drop into the socket of an Apple II keyboard encoder card. There sure is a market for that because many people who try to make a custom cable to plug the Apple II keyboard into the Apple-1 make a mistake and blow up the MM5740 (or on later keyboards, the AY-5-3600-931). And then they whine about the dead keyboard. And then they go shopping for an original MM5740 which is elusive --- these were mask programmed for a particular keyboard matrix and unless you can find exactly the right one it's a waste of money as it won't work (the MM5740 type code designates the "family" of keyboard encoders and the letters behind hit designate the custom mask programming which was different for each keyboard manufacturer). You can still find lots of MM5740 at IC brokers but in most cases with the wrong mask programming.  So somebody created this modern replacement. Which does not need -12V but of course still can be blown up if the cable to the Apple-1 has fatal mistakes. IIRC the replacement keyboard encoder is an open source project. But it's not economical for individuals to make their own PCB batches and to buy the programming equipment for the microcontroller. This is why making a complete keyboard like this "Newton" brand one is filling a void in the marktplace.

 

- Uncle Bernie

 

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Thanks for the info as always

Thanks for the info as always, Uncle Bernie.

 

I will have a look at my keyboards in my II+ computers. When it comes to the Briel Replica 1 Plus, I can swap out my single rail PSU for one of these if I need a -12v rail available: https://www.trcelectronics.com/View/Mean-Well/RT-50B.shtml

 

If I get a chance to try this I will start a separate thread for it.

 

Cheers,

Alex

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New batch of Datanetics Rev B keyboard set

Bernie is correct, -12V is not needed by the microcontroller chip and in fact the -12V line is disconnected from the microcontroller chip in the IC adapter PCB. In other words, this Datanetics keyboard replica should work with Replica-1 and any other Apple 1 replicas with just +5V supply and GND, it is just that the emulated MM5740 IC should be used instead of original IC. Furthermore, by replacing the original MM5740 IC with the emulated MM5740 IC, you can also use original Datanetics keyboard with Replica-1.

 

By the way, the keyboard itself also works with the original MM5740AAE/N IC, which I have verified, since the circuitry of the keyboard PCB was routed based on the original schematics and the original IC will still get -12V.

 

 

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New batch of Datanetics Rev B keyboard set

I am selling 8 sets of Datanetics keyboard sets, these are the last keyboard PCBs I have. I will reorder PCBs later on.

 

I posted 4 sets on ebay - can't list more as they cut my selling limit to 1/10 of the original as I used shipping services which they don't recognize.

Datanetics Rev B Keyboard set replica for Apple 1 I - not II lisa Newton NTI non | eBay

 

The other 4 sets are available by paypal invoice. $150 + $45 expedite shipping from Hong Kong. Please PM me if you need one.

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