Books 6502

KIM-1, AIM-65, SYM-1 and other 6502/65C02/65C816 related books.

A mix of English, German and Dutch books.

On my bookshelf I have quite a collection of books on the 6502 family.

Note that manuals and books that come with systems are shown on the pages of the corresponding system!

1984 Rockwell Data Book
6502 Software Gourmet Guide and Cookbook
6502 Users Manual
AIM 65 Laboratory Manual And Study Guide
Anwendunsgbeispiele fûr den Microprozessor 6502
Microprocessor_Fundamentals KIM-1
Best of Micro Volume 1 1978
Best of Micro Volume 2 1979
Compute’s Machine Language for Beginners
Compute’s The Second Book of Machine Language
Programming a Microcomputer 6502
Programmieren von Mikrocomputern CPU 6502 (Skriptum)
How to Build a Microcomputer .. and really Understand It!
Mikrocomputer ohne Ballast
Micro Principles KIM-1 user guide chapter 8
Digitaalschakelen met de KIM-1
6502 Assembly Language Programming
6502 Programmieren in ASSEMBLER
Microcomputer Experimentation with the MOS Technology KIM-1
6502 Machinetaal Subroutines
6502 Assembly Language Subroutines
Microcomputer experimentation with the AIM 65
Machine Language Programming Cookbook part 1
Machine Code for Beginners
microcomputer systems principles featuring the 6502 KIM
Beyond Games: System Software for your 6502 Personal Computer
Assembly Language Programming
Using 6502 Assembly Language
6502 Machine Code for Humans
Programming the 65816 including the 6502, 65C02 and the 65802
Programming the 65816 including the 6502, 65C02 and the 65802
Forth Programming
Programming the 65816
Programming and Interfacing the 6502 with Experiments
Synertek 1981-1982 Data Catalog
Synertek DataBook 1983
Third Book of OSI
TSC 6502 Games Package 1
TV Typewrite Cookbook
Zaks 6502 Anwendungen
6502 Games
6502 Applications
Advanced 6502 Programming
Fortgeschrittene 6502 Programmierung
Programmierung des 6502
Programming the 6502
6502 Applications book
Programmeren van de 6502
Microprocessor Interfacing Techniques
Microprocessor Concepts and Applications
Publisher: Lab-Volt
6502 Assembler-Kurs für Beginner
6502 Machine Code For Beginners
A low-lvel language for use on the MOS 6502 Microcomputer
6502 Microcomputer Programmierung
Programmieren in Maschinensprache 6502
The Giant Handbook of Computer Projects
First Book of KIM
The First Book of KIM-1 in PDF format
The First Book of KIM-1, part in text format
The First Book of KIM-1 in HTML format
Sources of The First Book of KIM-1 in source and papertape format, Jeff Tranter
First Book of KIM-1 for SYM-1
Rockwell Produktübersicht in deutsch
Rockwell Microelectronic Data Devices Catalog 1979
1981 Rockwell Electronic Devices Division Data Book
1984 Rockwell Data Book
1985 Rockwell Data Book
1987 Rockwell Controller Products Databook

Junior Computer ][

Junior Computer ][

Written by 2021 by Joerg Walke, visit his webiste for the most actual version!
The Junior Computer ][ is an expanded version of the original Junior Computer. To make it more useful, I’ve equipped it with 32KB RAM, 8KB ROM and an onboard RS232 serial interface for connecting a terminal or a printer. For the use with a terminal, I also wrote an extended monitor program thats included in the bigger ROM. The development of the Junior Computer ][ is still in progress, so some other features will find its way to the mainboard.

On the picture above, you can see the actual rev. 2 board of the Junior Computer ][.
The new revision 3 board has arrived!

…all components assembled and soldered

…and it works fine!
Its new features are: Up to 128KB RAM chips installable. 3 DIP switches to configure three additional 8KB RAM banks. Maximum of 51712 Bytes usable with 64KB RAM chip. Auto reset at power on. A power switch (oh yeah). Usable Memory for string buffers in the address area of the ACIA.

The Computer is divided into two parts. On the left side are the main computer components. The 6502 CPU, 6532 RIOT (RAM, Input/Output and Timer), ROM (8 KB EPROM), RAM (32 KB SRAM), the 1MHz quarz cristal and some 74LSxx logic chips for address decoding and clock generation. There is also a double timer chip on the lower left corner for debouncing the Reset (R) and Stop (S) keys. On the top lies the (in the picture not populated) expansions connector. And on the bottom side there is a connector for the two 8 Bit I/O ports coming from the 6532 RIOT. A small transistor amplifier on port B0 can be used to drive a loudspeaker, to make some simple noise.
The input/output components of the Junior are on the right side of the PCB. There is the hexadecimal keyboard, for entering the program addresses and data. And there are also some control keys. Above the keyboard is the six-digit, 7-segment display for showing the addresses and the data bytes as hexadecimal coded numbers. The display can also be switched off, if not needed. Keyboard and display is controlled by the two 8-bit I/O ports of the RIOT, by alternately polling the keyboard and repeatedly writing each single digit of the data to be shown on the display. On the top of the I/O side is the 6551 ACIA (Asynchronous Communications Interface Adapter) chip and a level shifter for the RS232 serial interface signals. The little quarts aside the ACIA is for the baud rate generation, which ranges from 50 to 19200 Baud.
I built the first prototype in July 2020 on a breadboard, followed by the rev. 1 PCB in August 2021.

The rev. 2 board was necessary, because unfortunately the distances between the input keys were a little bit too narrow. Also the rev. 2 board had some issues. But it worked fine for me. After publishing the JC][ on the Classic Computing forum (, I found some people who were interested in it. That charged me to make some further expansions and to make it a little bit more useful for others. The revision 3 board with some improvements is now on the way, as is new software.
The schematics and Gerber files for the PCB and of course the ROM images and the 6502 Assembler source code files are freely available on the download section. So feel free, to make your own Junior ][ and have some fun with 8 bits.

Programming the Junior Computer ][

Programming the Junior is quite simple:
Apply power and press the (R)eset switch. The display turns on and shows a random memory address (four digits) and its content (two digits). The Junior Computer ][ and its predecessor are both programmed in raw 6502 machine language. That is, each CPU command is entered in its numeric representation as a hexadecimal number. For example, 4c 00 F8 means: Jump (4C) to absolute location F800. 16-bit values such as memory addresses are written as the lowest byte first, so the byte representation 34 12 in memory represents the 16-bit value 1234 in hexadecimal.
To enter some data, you first have to type the address, were the data should be located. To do so, press the (AD)dress key and type in the four hexadecimal digits (16 bits) of the memory address location. Then press the (DA)ta key and type the two hexadecimal digits (8 bits) of the data. If you make a mistake, simply type in the new value. To enter data in the immediately following address, press the + Key (in my picture above, this is the down arrow key – because I just hadn’t a + keycap) and enter the new data.
To examine any address, you just have to press the (AD)dress key again and type in the address you want to visit. By pressing the + key, the direct successor address is displayed. Pressing the GO key executes the program at the currently displayed memory address. There is also a Edit mode where you can insert and delete data, and automatically calculate branch and jump addresses. To use this mode, please refer to the Junior Computer Book 2.
Another way to enter programs is, to use the extended (terminal) print monitor program. First you have to connect a VT100 compatible terminal to the RS232 interface and set it to

9600 Baud, 8 data bits, no parity, 1 stop bit

To start the monitor program, press the (AD)dress key, type in the address F800 and press GO. On the terminal display, you should now see something like this:

                                  Junior Computer ][

Print Monitor
2021 by Joerg Walke

(M)onitor  (L)oad  (S)ave  (A)ssembler  (B)asic ?

For now Monitor is the only selectable choice (but the rest will come soon, hopefully), so type M on the terminal keyboard to enter the Hex Monitor. The Display is cleared and a * prompt is shown. All input is non case sensitive, so typeing M or m is the same.
To examine the content of a single address, just type in the address as a hexadecimal number and press the Return key. The address and its current content is then shown.


F800- 4C

To view a hole block of data, enter the start-address and the end-address of the block to be shown, divided by a . (dot).


F800- 4C DC F8 A4 F8 B1 F6 E6 
F808- F8

To enter new data, type in the address where the data should be written, followed by a : (colon), followed by the single data bytes.

*200: 4C 00 F8

0200- 03

Execute a program by typing the start address followed by a G


0200- 4C

To exit the Monitor and to go back to the main screen of the monitor type


and then press the Return key.
If you want to go back to the standard Junior Monitor just enter


(followed by Return) which leaves the terminal screen as a Zombie without a function and enables the 7-segment display and the hex keyboard.
That’s it. If you are interested in learning more about programming the 6502 and the Junior Computer, please refer to the MOS 6502 Datasheet and the Junior Computer books.

Downloads Junior Computer ][

Downloads Junior Computer ][

Elektor Junior Paperware 3 in German!

Thanks to Martin Seine I have added the Paperware 3 in German book to the Junior book collection.


Elektor 6502 clock

In 1981 and 1982 the magazine Elektor (Elektuur) published a small 6502 system. Small since it only contained a 6502, a 6532 RRIOT and a 2716 2K EPROM and some logic IC’s and powersupply, all on a small PCB.
Several applications around this baord were publsihed, like a DCF77 clock, a general purpose clock, and a darkroom computer. Also a talking clock baord, around the speech IC UAA1003 was published.

Recently I obtained a DCF77 talking clock system, and I took it apart and cleaned it up to experiment with the boards, and I do not want to use the heavy lineair power circuits anymore. See the bottom of the page how it looked in the original form.

Circuit of CPU module, 6502, 6532, 2716, clock, power supply, decode logic

LEDs and keyboard of clock module

LEDs and keyboard of darkroom module

CPU board

Talking clock with UAA1003

LED and keyboard of talking DCF77 clock

Talking clock circuit UAA1003

Memory map

Memory map, only decoded up to A11, so everything is mirrored in the 64K memory space in 4K blocks.

0000 - 007F zeropage/stack
0080        6532 registers
0400        latch 4 bit output
0800 - 0FFF 2k ROM 2716
FFFA - FFFF vectors in ROM

Magazine articles

Elektuur/Elektor published the articles around this 6502 system in 1981 and 1982. Not all were published everywhere. The DCF77 clock was not published for example in the UK (and that makes sense, nor reception there from Frankfurt). Only in the Dutch articles, sources were published in addition to the hex dumps of the firmware.
Here the scanned articles

Dutch articles:
– DCF77 clock
– Alarmclock with listing of sources
– Doka computer
– Errors in articles
German articles:
– DCF77 clock
– alarm clock
– Duka Clock
EPROM image

Elektor clock EPS-82137_ checked
English articles:
– 6502 housekeeper
– Talking clock
– Darkroom computer
UAA1003 ITT datasheet

Listing of DCF77 clock

Listing of changes for alarmclock

Original DCF77 housing


PC utilities updated

The PC utilities page has seen an update of th4 Conversion hex formats utility.

Programs to manipulate the binary and hex formatted files of interest for SBC owners. Intel hex, MOS papertape, Motorola S-record, binary, hex conversion fort eh 8 bit world.
Runs on Windows, Linux, Mac due to Lazarus and Freepascal. Source included.


Elektor Computing 5 German

Thanks to Martin Seine I have added the German evrsion of Elektor COmputing 5, dedicated to the EC65 systen, Z80 card, 65818 etc.

And have a look at the EC65 Z80 card page also



Z80 Elektor articles

A new Elektor page in the Z80 department: Z80 CP/M with ROM (thanks Martin Seine!)cards for the Elektor EC65 bus, mini card, universal card.


Multi-purpose Z80 card

Universal Multipurpose Z80 card. Elektor 1992.

Universele Z80 kaart deel 1 en 2 Dutch
Multi-purpose Z80 card part 1 (English)
Multi-purpose Z80 card part 2 (English)

Mini Z80 System

A very small but versatile Z80 system. Elektor 1992.

Mini Z80 System
RAM extension for Mini Z80 System

EPROM Programmer for Z80

Simple EPROM  programmer for the Z80 for 2716EPROMs. Published in January/February 1984.

Scan in Dutch, German and English.