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KIM-1 clones and replica’s

The KIM-1. my first computer. Still have it, and it is still operational.

But I fear to use it for experiments and daily use, it is too valuable for me.

So I invested in KIM-1 clones and replica’s:
– Micro-KIM by Vince Briel
– KIM Clone by Bob Applegate, Corsham Technologies
– MOS KIM-1 Reproduction by Dave Williams
– KIM Uno by Oscar Vermeulen

Each has it advantages. And not all are still for sale.
Corsham is till in business and has an awful KIM Clone, with motherboard, I/O card, experimenters board and SD file system. A real enhanced KIM-1 on real KIM-1 hardware.
The KIM Uno is also available, affordable,now an emulator on an Arduino, soon on ESP32. Fun to have a KIM-1 look and feel.

All are documented on the KIM-1 replica’s and clone page.



KIM replica’s and clones

I have several KIM replica’s or clones.

The CPU is of course a 6502 at 1 MHz crystal clock frequency. The edge (Application and expansion) connectors are physically and logical identical. And they have the KIM-1 ROMs!

Since 6530 RRIOT ICs (the 002 and 003 variant) are not available anymore, the same solution as in the other clones is chosen: a 6532 RIOT with a 2K EEPROM and some logic ICs (3) to get a hardware solution that makes it look exactly the same for the KIM-1 ROM software. The PCB is of course new design, not the typical 70ties KIM-1 rounded lines PCB design.

The result is great: it feels, looks and operates as an original KIM-1 with hex keyboard and LED display.
First Book of LIM programs run, All KIM-1 sofwtare runs, Microsoft KIM-1 Basic and Microchess run, when additional RAM is connected.

Corsham KIM Clone

MOS KIM reproduction

KIM Uno

Micro-KIM

Pocketerm

The PockeTerm is a 4″ X 2.5″ single board terminal that uses a VGA monitor and a PS/2 keyboard for its input and output. Dual serial ports gives the user the option of transferring data to/from a PC while still connected to the host device. This terminal was designed to work with vintage computers but is compatible with most systems including Unix and Linux systems. A low cost color choice terminal that has VT-100 compatible commands for controlling cursor and screen functions. Want to program the propeller microcontroller or install an update to the firmware? No problem, just connect the PockeTerm to your PC, run the Propeller Tools software and you can program it from your PC, no expensive Prop Plug required.

The PockeTerm has a full featured screen with Function key status at the bottom of the screen. Click on the image for a full size photograph of the screenshot.

CTRL-F1 Selects Baud Rate
CTRL-F2 Changes text color of the main display section
CTRL-F3 Turns on/off the 2nd serial port that connects to a PC.
CTRL-F4 Force incoming data to 7 bit ASCII. Strips the 8th bit, required for some systems
CTRL=F5 Change cursor type. Choose from underscore, solid block, or none. Also, choose from blinking or not.
CTRL-F6 Add line-feed to carriage returns

Documents

Pocketerm Setup and Users Manual 2009
Pocketerm Setup and Users Manual V3 2009
Pocketerm Circuit diagram
Pocketerm Bill Of Materials
Pocketerm Firmware
Pocketerm CD

PS/2 keyboards

I have succesfully assembled the kit, the manual guided me just fine through the steps. Took me just over an hour.
The PockeTerm worked right away. Thanks to mfortuna’s tip, put jumpers in 1&2 and 5&6, and testing is independent of cables and computers to connect.

A standard keyboard with PS/2 worked. What did not work was my mini-USB keyboard (standard PC keyboard without numerical pad, and smaller size, like notebook keyboards) connected via an USB to PS/2 converter. The USB keyboard is ok, works with the PC’s and the Apple 1 kits via the USB-PS/2 dongle. I bought it because the smaller size looks better with the small computers and takes less desk space With the scope I found the PS/2 clock/data line (cant remember which one), to be open, as if nothing connected. So something is missing to make the USB device come alive. I googled around and found this: http://www.parallax.com/Portals/0/Downloads/docs/prod/edu/28060-PS2Adapter-v1.0.pdf
In it I saw a schematic how to connect a Parallax mini PS/2 keyboard, and it was different from the PockeTerm PS/2 interface. It has additional 10k pull-ups connected to the PS/2 clock and data. I soldered in the two 10k’s and the mini keyboard came alive!

Program the Propeller Notes by Vince Briel

  1. Go download propeller tools from parallax here: http://www.parallax.com/Portals/0/Downloads/sw/propeller/Setup-Propeller-Tool-v1.2.7-(R2).exe
  2. Install propeller tools
  3. Place the firmware directory from your PockeTerm CD onto your hard drive here:
    C:\program files\parallax inc\propeller tool v1.2.7 (r2)\
  4. Connect your PockeTerm to the RS232 port labled PC and turn on your PockeTerm.
  5. Under the propeller tools program click on the section File and find the firmware directory you just copied onto your hard drive and select the file
    PockeTermV.905.spin
  6. Press F11 on your PC keyboard and the propeller tools will compile and attempt to find a Propeller chip connected to a serial port on your PC. If your
    connection is good it will program the RAM first on your Propeller chip then program the EEPROM.

The PockeTerm makes a really good development board for learning how to program the Propeller chip. For more information on programming the Propeller,
please visit the Parallax forums here: http://forums.parallax.com/forums/default.aspx?f=25
The above steps will program the Propeller with the code that is now resident on the EEPROM onboard the PockeTerm. Change step 3 to the location of the program you wish to insert onto the PockeTerm.








Replica 1 software and hardware articles

A collection of articles and projects around the Replica 1.

Rebus

REBUS Replica 1 Hardware Extensions
ACIA, Flash, Apple II sound
Ken Wessen
Apple II sound circuit
Replica Quick reference by Jeff Trenter
Krusader Ken Wessen’s assember IDE
Archive with many variants, sources, versions
Krusader 1.2.1 source for use with an ACIA
Applesoft Lite archive
EWoz extended WOZ monitor with hex file upload
Jeff Tranter’s large collection of 6502 articles
Micro-KIM, Replica 1, and much more. A real treasure collection, original here!

EEPROM programmer circuit (as featured on the Multi I/O board)
EEPROM circuit
Here’s a 1 chip EEPROM programmer for somebody wishing to copy their EEPROM or create their own data. In keeping with the replica 1 theme, it is a down and dirty solution requiring few connections. All the connections listed on the EEPROM go to their listed connections. A 74LS00 is all that is required to program an EEPROM.

This attaches to address A000-BFFF and is direct addressing. Simply write to the address to store the data. You should give a slight delay after your write since it takes 200ns to write a byte into an EEPROM. I do a short loop in basic

FOR I=1 TO 2:NEXT I

That does the trick. I tested this circuit out and had 0 errors when writing.

Replica 1 Cassette Interface

In 2007 Vince Briel tried to get a replica of the Cassette board, as designed by Steve Wozniak, operational. Another example of the genius Steve Wozniak, minimal hardware, 256 byte program. Two revisions, he did not have much luck with this. Reports indicate this has to do with insufficient quality of the power supply lines.

Original Apple 1 Cassette Interface Manual
A real userguide as can be found at the site of San Bergmans
Mimeo Cassette Interface and Operations Guide

Software
Archive with disassembly and source files of the Apple 1 Cassette Interface.



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Replica 1 Multi I/O Board

The Multi I/O Board, 2007, gives 2 8 bit bi-directional ports with 4 handshaking lines, a 6522 VIA,, a true RS232 serial port, a 6551 ACIA, with speeds up to 19,200 BAUD, and a 8K EEPROM programmer to store data or programs. There is a socket to add your own Speakjet voice chip that works in conjunction with the serial port to make your Replica 1 or Apple 1 speak!
Software included to let the WOZmon operate over serial.

Multi I/O board Setup and users Manual
multiboard_schematics.pdf


Replica 1 slot expanders

Three slot expander

Available first in 2006 for the SE and continued to the Plus. One side for the 40 pin connector, the other side a real Apple 1 slot.

Note that sometimes the 40 pin flatcable connection is not reliable and gives CFFA1 I/O errors. A thick extra ground wire between the Replica 1 and the slot expander solves this.


Slot Expander I board manual

One slot expander

A single slot expander, one Apple 1 slot, to be placed upon the 40 pin box connector.

Replica 1 Plus

The latest designed and sold by Vince Briel: The Plus
Now licensed to and for sale at ReactiveMicro

Vince Briel said this about the Plus:

Based on the the fastest selling replica, the replica 1 tenth anniversary edition, the plus has improvements over the TE that make programming and power issues a thing of the past. Now you can power your replica 1 right off your PC or Mac or Tablet with the USB interface. With drivers installed, you can use a terminal program for sending/receiving programs or just use the terminal interface as your display and keyboard if you want. For those who prefer the stand alone feature, you can still use a composite monitor or TV and PS/2 keyboard. 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. Firmware changes now allow backspace or the original _ to be used just by selecting CTRL and F1. No more fighting backspace issues. Two versions of ROM’s onboard to select from! Yes, the original apple 1 with BASIC and now the Woz monitor and Applesoft lite can be used by adding a jumper! Enjoy floating point BASIC ported from the Apple II.

Replica 1 Plus Setup and users Manual
Replica 1 Plus Schematic
R110REV03.zip firmware Propeller

Replica 1 TEN

To celebrate the 10 years since the first Replica 1 appeared i9n 2004, Vince Briel did a limited run of the Replica 1. A red PCB, reduced IC count due to more integration into the Parallex Propellor made a smaller board.
The limited run was sold out quickly, the nearly identical Replica 1 Plus was the next Replica 1, still available in 2021.

The announcement of the Ten by Vince Briel:

As previously mentioned in A2central.com the new replica 1 tenth anniversary edition is here. It’s hard to believe it has been 10 years since the replica 1 was created. In celebration of 10 years of kits, we have a limited edition replica 1 ten board. The new design is our sleekest and most modern design ever. The mini USB interface is not only a power source, but has a built in USB to serial interface allowing you to have a virtual COMM port on your PC. You can run your entire replica 1 from a USB port on your PC or from a USB power supply.

The new replica 1 ten limited edition has a unique red color distinguishing it from prior versions. As such, we are limiting it to only 50 hand serial numbered units. Why 50? Well, that is the number of apple 1 computers believed to still be in existence. In order to maintain an economical kit with today’s rising component prices, we found ways to reduce components and made some hard choices too. Gone is the ATX power supply option along with the 40 pin replica 1 header, however, there will be ways to get these features as needed. Don’t have a USB power supply, we now offer a universal USB power supply

The new design allowed us to eliminate the 1MHz oscillator and now the Parallax Propeller controller generates the system clock. We added a larger EPROM so you can now select between the original BASIC or the new Applesoft lite. We were also able to reduce chip count using the Propeller to handle critical I/O glue logic processing. All these changes makes it possible to not only maintain the price, but also makes a smaller, more efficient board.