Connect a PC-Keyboard to your ATARI 800/130!
 

all common PC Keyboards (MF2 Standard) useable 99% ATARI-compatible several keyboard layouts (languages) simply to install, no tuning ATARI keyboard can be used the same time macro memory for up to 60 keystrokes, will be hold after power off AKI software can be updated New professional manufactured board now available ! No more soldering on the POKEY (only if POKEY is socketed) passive components in SMD package no small SMDs, so it can be soldered by hand it can be placed inside the shield most connections are plugable, only 5 soldering points socket for optinally macro EEPROM (up to 8KByte) Sorry for my bad english, if theres somebody who can help me with a better translation contact me !!! MacFalkner@aol.com

1. some short infos

AKI is a small interface platine to connect the ATARI 800/130 with every common PC-AT-keyboard (also Windows 95 keyboards). The old ATARI keyboard will be useable the same time. The AKI interface and the 5c DIN connector / or PS2 connector are build inside the ATARI. Its simple to build in cause there is only a small soldering work to do. The interface is placed 'up-packed' to the ATARI keyboard chip (POKEY), therefore the connection is very solid. AKI is 99% softwarecompatible cause it is simply parallel switched to the old keyboard. The POKEY chip will not be able to detect differences in the signals. The compact layout allows to put the interface direct up to the POKEY (ca. 25x50mm). The AKI CPU can be updated with new firmware*

* The PIC must be placed into an PIC programmer device, also programming software will be required.
 
 

AKI component side (new layout)	AKI soldering side (new layout)

 

One of the first tries of the AKI hardware :-)	handmande board of the new layout with POKEY, EEPROM and PIC. Some SMDs are on the soldering layer

2. Build in

First, before you start, you will need an PC-keyboard. They are very cheep this time, its no problem. Who wants to use an ergonomic cherry keyboard can do this also :-). Look for 101/102 keys and MF2 standard. 5p DIN and PS2 can be connected. All keyboards common this time, do this !!! Newbies better use the DIN connector cause the PS2 is more difficully to sold.

All work should be done when the ATARI is switched off. Also a basic electronic tool set should be availaible (theres no need of an oscilloscope etc.).
 
 
 

Now follow the steps:
 

Open the ATARI, put a hole for the connector. The connectors should be placed from outside, then you will have no problems with the fixing holes. A solid mechanical connection will be recommended. There isnt an exact position giving for the connector. Everybody can choose its own place. You should use short cable connections to the AKI. Lengths under 50cm are uncritical. Attention! A longer shortcut of the power supply can be bad for the ATARI-supply unit, a longer swap of the power supply lines will be bad for the AKI CPU (PIC) and can kill the PC keyboard. A swapping of the datalines will have no destroying effect (normally :-)).

The figure shows the insertation of an 5p DIN connector in the ATARI 800XL. Its placed between the SIO connector and the bus expansion port.
 
 

The AKI interface is placed 'up packed' to the POKEY chip (10 soldering positions).It will be nice to have an ATARI with sockets for the chips !!! Place out the POKEY, sold on the AKI and place the POKEY back. If your POKEY have no carrier are there 3 variants: The first one, you sold the AKI direkt onto the PIC, this is something complicated cause theres not much space to sold. The second is you place a socket for the POKEY, but this is much work and should only be done from professionals. The third version is you sold an 40p carrier up to the PIC an plug the AKI inside. In this case you must put a hole in the ground shield (the ATARI can also work without the shield, but there can be reduced video picture quality). Eventually, an capacitor, right under the POKEY must be layed down.

Insertation of the first prototype in the ATARI 800XL.
 
 

Connecton of START, SELECT and OPTION in an ATARI 800 XL (the 3 resistors are right down outside the ground shield).
 
 

Connecting RESET line (gn / wh), right under the AKI.
 
 

Signal definition	ATARI 800XL / 130XE
START	left side from R134
SELECT	left side from R135
OPTION	left side from R136
RESET	left side from L14

Now, also a connection to a switchable RAM-Disc can be done. This can not be specified without knowing of the inserted RAM-Disc technology, see section "AKI and RAM Extensions" for more details.
 

Now turn on your ATARI, test the function of the old ATARI keyboard. If it works, plug in the PC keyboard and start ... You can start the ATARI build in keyboard test, but this will not be a good indicator to test the PC keyboard. If only one key dont work, the defect is placed in the PC keyboard. If nothing works the whole installation must be checked. Latest, after plug out the PIC of the AKI, the old ATARI keyboard must work.

Some tips for troubleshooting:

• First: on a selfmade platine all connections must be tested for micro breaks and bridges. Check the polarity of the diodes! The 'nose' of the PIC must be placed in direction to the keyboard connector!
• Check the supply voltage direct between PIN5 (GND) and PIN14(+5V), there must be 5V +-10%, is this wrong check the connections to the POKEY
• On the keyboard connector also 5V must be measureabled. On the PC keyboard, after switch on, the three lamps should flash on (PC keyboard selftest). If the supply is ok. and theres no flashing, the PC keyboard is defect or a very old one.
• Check with a logictester on RESET PIN4. There must be a hi, if not check R1 and C1 for bad connections.
• On PIN 15 (16) must be pulses (2 / 4 MHz), if not, check the crystal and PIC CPU (is the PIC correct programmed ?).
• On PIN 12 and 13 must be frequences with 31KHz and 500Hz, if not test the connections to the POKEY.
• On a keypressing on the PC keyboard, on PIN 2 and 3 must be a pulse raster, also on output PINS 10 and 11, if not check the datalines to the keyboard (CLK and DATA swapped ???, is the PIC correct programmed, PIC defect, polarity of diodes correct?)
• On pressing F5, F6, F7, F8 (also SHIFT-F8) on PIC pins 6,7,8,9,17 a static low must appear, on PIN 17 (only RAMDISC) the signal must change after RESET / SH-RESET (is the PIC correct programmed ?)
• Now check for the same signals on (START, SELCT, OPTION, RESET), if theres no signal, check diodes and its polarity.

 

3. Keyboardlayout

fig. 8: PC-MF2-standardkeyboard (english Version, keys 42 and 45 added on german layout)

The PC-keyboardlayout is mostly identic with the printed symbols on the keys with the german / english (american) keyboard. The english layout is mostly common with the original ATARI layout, maybe some german PC users prefer her layout.

Keynumbers with several language functions: 3,7,8,9,10,11,12,13,22,27,28,40,41,42,45,46,53,54,55.

Here are the special funtioin keys:
 

PC key	ATARI-Emulation
CTRL-ALT-DEL	RESET
F1	ATARI (1200er) F1 key* , also SHIFT / CTRL
F2	ATARI (1200er) F2 key* , also SHIFT / CTRL
F3	ATARI (1200er) F3 key* , also SHIFT / CTRL
F4	ATARI (1200er) F4 key* , also SHIFT / CTRL
F5	START
F6	SELECT
F7	OPTION
F8	RESET
F9	free
F10	HELP
F11	INVERS
F12	BREAK
ALT-F9	sending macro 1
ALT-F10	sending macro 2
ALT-F11	sending macro 3
ALT-F12	sending macro 4
CTRL-ALT-F9	recording macro 1 (max. 15 keystrokes)
CTRL-ALT-F10	recording macro 2 (max. 15 keystrokes)
CTRL-ALT-F11	recording macro 3 (max. 15 keystrokes)
CTRL-ALT-F12	recording macro 4 (max. 15 keystrokes)
ALT-F1	sending AKI versionnumber
ALT-F2	sending fixed macro ‘POKE’ (for a faster keyboard in BASIC)
ALT-F3	switching between german and english keyboard layout (stays after power off)
ALT-F4	stop macro recording

* there are some ATARI models wich have keys F1...F4. These keys are supported from the ATARI OS (also 800/130er OS!) and have following functions:
 

F1	Cursor up
F2	Cursor down
F3	Cursor left
F4	Cursor right
SHIFT-F1	goto top of screen (HOME)
SHIFT-F2	goto end of line
SHIFT-F3	goto start of line
SHIFT-F4	goto bottom of screen
CTRL-F1	switchs off keyboard until pressing CTRL-F1 (Attention trap!!!)
CTRL-F2	switchs off screen until pressing any key
CTRL-F3	toggles keyboardclick
CTRL-F4	toggles charset (graphic / international)

4. Softwarecompatibility

Like said above, AKI is 99% softwarecompatible, cause the ATARI is not able to detect differences to the original keyboard. Here are some differences (the 1 percent):

• The keys START, SELECT, OPTION, RESET, also BREAK, SHIFT and CONTROL, are sampled in combination from the atari. A standard PC keyboard cant sample combination codes*. Pressing more then one of these keys at the same time, under several circumstances can't be detected. The AKI user will not be able to press START, SELECT, OPTION and RESET at the same time (F5, F6, F7, F8). On a tested FUJITSU N860-8725-T853 and a NCR H0150-STD1-12, START, OPTION and RESET can't be pressed at the same time (is there anybody working with cassette drive and an AKI ?). Combinations from not more then 2 keys are working correctly. For other crazy keystrokes use the ATARI keyboard. Im not sure that the 100% compatible TRANSKEY can handle these situations :-).
• Through the several language keyboardlayouts it can be that some chars are not reachable. Mainly this is important for users of the german layout and an english keyboard hardware. On the english hardware the key 45 is not present, therefore a '|' cant be reached under german softwarelayout. Other problems can occur on other hardware/software combinations.

• Keyboard macros are sended by the AKI. In the actual version the sending speed is not configureable, it can be that slow ATARI programs ignore some keystrokes sended by macros. The macro sending speed is tested in the standard BASIC there its ok. Perhaps in a new software version, there is the option to change macro sending speed.

5. AKI and RAM-Expansions

There is an output on the AKI interface, especially designed to switch RAM-Disc systems with a bank switching option. The 2 ATARI switching is very easy with the AKI. Press RESET for the first one, SH-RESET for the second. The output is switched some time after activating the RESET signal, so a sure switching is guaranteed. There are many several extensions for the ATARI available, so i cant give an exact description, how to do. Mostly the OS / RAM selection is done by an mechanical switch. The following methods are common:

The AKI ouput has an so called 'open collector' therefore not all variants are uncritical to connect. Variant "A" gives no problem, the AKI switching output can be directly connected to the input of the extension (take care that the resistor dimension is >1KOhm). Dont connect to variant B or C, destroying the PIC can be result. If you have variant B or C in your ATARI, rewire it to variant A, the switching ability stays the same. Now you can contact your AKI output additianally.

6. Technical infos

The AKI is a one chip processor system with an PIC processor with 64 byte internal EEPROM. The hardware is mostly the standard application for the PIC processor. The PIC is receiving the serial AT keyboard codes, interpreting it and simulate an keystroke in the ATARI keyboard matrix. The SHIFT and CONTROL keys are 1:1 software connected. The supply current is typical 20mA and the PC keyboard needs 70mA-160mA, and its no problem for the ATARI power supply.

Schematic (GIF, 30KByte, 300dpi)

Layout (GIF, 12KByte, 300dpi),  new SMD Layout (GIF, 20KByte, 300dpi)

Hexfile for PIC-Programming, actual Version! (Intellec8, 6KByte)

The following components are needed:

• a programmed PIC in a DIL package (4MHz version), a socket will be recommended for updates
• 6 small signal diodes, for instance 1N4148
• 1 crystal (approx. 4MHz)
• R1 resistor 100KOhm
• R2 resistor 2,2 ... 10KOhm
• C1 capacitor 100nF
• 4 p PF connector, 2.54 mm (1/10")
• 1 platine

Funktionsweise von AKI, Matrixcodes (Scancodes) der ATARI-Tastatur ... u.v.m ! (TXT, 7KByte)

Liste mit allen bisher durchgeführten Änderungen (Bugreport) !

7. Selling, Handling, Quality and further development

This is a hobby project of mine, that is free availaible for all ATARI freaks. This document and all linked files are ‘F r e e w a r e’ and can be copied free or for a selfcost price. The copying of CAD and assembler sourcefiles is   n o t   a l l o w e d . Reproducing the hardware is free for single boards for private/friends. The reproducing for commercial is    n o t   a l l o w e d .

Please contact me for availability / delivery outside germany MacFalkner@aol.com
 

AKI complete and tested, incl. all wires and plugs		30,- Euro/US$*
AKI PIC programmed with the newest software version		15,- Euro/US$*
AKI board (empty), double sided, solderstopmask		15,- Euro/US$*

* all prices without P+S.

I will be enjoyed for tips to upgrade the PIC software or reported bugs, or contact me if you have some questions: MacFalkner@aol.com

Sources:

• SAMS computerfacts (ATARI schematics), copies from ABBUC-Bauplanservice, ABBUC-HOME
• Der ATARI mit IBM-Tastatur (TRANSKEY), copies from ABBUC-Bauplanservice, ABBUC-HOME
• PC-Tastatur am ATARI XL (description of the ATARI matrixcodes), copie from ABBUC-Bauplanservice, ABBUC-HOME
• National Semiconductor: Application Note 734: 'MF2 Compatible Keyboard With COP8 Microcontrollers', NS-HOME
• Motorola: Application Note 1723: 'Interfacing MC68HC05 Microcontrollers to the IBM AT Keyboard Interface', MOTOROLA-SEMICONDUCTOR-HOME
• PIC16C84 from Microchip, MICROCHIP-HOME

• Burkhard Rau (Media-Inside) for beta test and Nörgeln,
• the A.B.B.U.C. - Bauplanservice for the technical documents,
• Erhard 'Floppy-Doc' Pütz for the betatest, the infos about TRANSKEY, and the inspiration to make this side!.