07 March 2016, 23:15 | #1 |
Registered User
Join Date: Feb 2016
Location: Homeless
Posts: 65
|
Amiga 500 Keyboard Schematic Mitsumi
I couldn't find a schematic for the A500 keyboard, so I've drawn one myself...
Code:
Amiga 500 Keyboard Schematic (nocash, 04 Mar 2016) .-------------. | RAM_VCC|1 --VCC .--R9--VCC /X7 /X6 /X5 /X4 /X3 /X2 | /Y15 PD7|2 -->----.--'- - - - - - - /Y15 N/A N/A N/A N/A N/A N/A | /Y14 PD6|3 -->----|---------------- /Y14 NUM* EUL CAPS TAB `~ ESC | /Y13 PD5|4 -->----|---------------- /Y13 NUM+ Z A Q 1! NUM( | /Y12 PD4|5 -->----|---------------- /Y12 NUM9 X S W 2@ F1 | /Y11 PD3|6 -->----|---------------- /Y11 NUM6 C D E 3# F2 | /Y10 PD2|7 -->----|---------------- /Y10 NUM3 V F R 4$ F3 | /Y9 PD1|8 -->----|---------------- /Y9 NUM. B G T 5% F4 | /Y8 PD0|9 -->----|---------------- /Y8 NUM8 N H Y 6^ F5 | MOS XTLI|10-------|----.--C12--GND | | | | | | | 6570 XTLO|11-------|--. Y1 | | | | | | | -036 GND|12--GND | '-'--C13--GND | | | | | | | /Y7 PC7|13-->----|---------------- /Y7 NUM5 M J U 7& NUM) | 6502 /Y6 PC6|14-->----|---------------- /Y6 NUM2 ,< K I 8* F6 | /Y5 PC5|15-->----|---------------- /Y5 ENTR .> L O 9( NUM/ | /Y4 PC4|16-->----|---------------- /Y4 NUM7 /? ;: P 0) F7 | /Y3 PC3|17-->----|---------------- /Y3 NUM4 N/A '" [{ -_ F8 | /Y2 PC2|18-->----|---------------- /Y2 NUM1 SPC EUR ]} =+ F9 | /Y1 PC1|19-->----|---------------- /Y1 NUM0 BS DEL RET \| F10 | /Y0 PC0|20-->----|---------------- /Y0 NUM- DOWN RGHT LEFT UP HELP | CNTR|21--GND | | | | | | | | CAPS_LED PB7|22-->----|-. | | | | | | | /LAMI PB6|23<------|-|-- key | | | | | | | /LALT PB5|24<------|-|-- key | | | | | | | /LSHT PB4|25<------|-|-- key | | | | | | | /CTRL PB3|26<------|-|-- key | | | | | | | /RAMI PB2|27<------|-|-- key .--C3--GND | | | | | | | /RALT PB1|28<------|-|-- key +--C4--GND | | | | | | | /RSHT PB0|29<------|-|-- key +--C14-GND | | | | | | | MAIN_VCC|30-------|-|--------'----VCC | | | | | | | /X7 PA7|31<------|-|--------------------' | | | | | | /X6 PA6|32<------|-|-------------------------' | | | | | /X5 PA5|33<------|-|------------------------------' | | | | /X4 PA4|34<------|-|-----------------------------------' | | | /X3 PA3|35<------|-|----------------------------------------' | | /X2 PA2|36<------|-|---------------------------------------------' | SIOCLK PA1|37-->----|-|----------------------------------------------. | SIODAT PA0|38<->----|-|---------------------------------------------.| | /RESET /RES|39<------|-|-------------------------------------------. || | /NMI|40--VCC | | ______ | || '-------------' | '-------------R10---E|Q2 NPN\ | || .--------------------' |BC458C |B--R4--/CAPS | || | .------------. VCC--R7--. GND--C|______/ LED | || '--> 1|/TR 74 RC|15---------+ | || VCC-- 2|TR LS C|14---C10+--' .------------. VCC--R8--. | || VCC-- 3|/RST 123 Q|13------------>9|/TR 74 RC|7 ---------+ | || VCC--16|VCC /Q|4 -- VCC--10|TR LS C|6 ---C11---' | || '------------' VCC--11|/RST 123 Q|5 ------. | || GND-.-8|GND /Q|12-- | | || /Y15 pulsed alive VCC--C7---' '------------' | | || .------------------------------------------------------------' | || | _____ | || | /LAMI-- 3| NOR \ VCC--R1--. ______ | || | /CTRL-- 4|74LS27|6-----------'--E|Q1 NPN\ .--R3--VCC | || | /RAMI-- 5|_____/ |BC458C |B---+ | || | GND--C|______/ +--C9--GND | || | .-------------------------------------------------' | || | | .-----C6-------. .---------------------------' || | | | .--------. | | .--C2--GND || | | GND-'-1|GND VCC|8-'-VCC | .-----'-----------'| | '-------2|TRIG Dis|7---.---+---R2--VCC | | .--.------------' | .-------3|OUT Thr|6---' '--+C5--GND | | | '--C1--GND | | VCC---4|/RES CV|5---C8----------GND | | | | | | HA17555| | | | .----. | | '--------' | | '----[FB1]-1|KCLK| | | _____ | '-------[FB2]-2|KDAT| | +----- 9| NOR \ /RESET to amiga | .-------[FB4]-3|/RES| | +-----10|74LS27|8----------------------------------' VCC--[FB3]-4|+5V | | +-----11|_____/ | --5|NC | | | _____ | RED LEDS GND--6|GND | | +----- 1| NOR \ /RESET to 6502 | GND--|<|--|<|--R6----7|PWR | | '----- 2|74LS27|12---------------------' GND--|<|--|<|--R5----8|DRV | '--------13|_____/ GREEN LEDS '----' amiga 1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 cable .----------------------------------------------------------------. |X4 X6 X3 X2 VCC CTL LAL Y14 Y12 Y10 Y8 Y6 Y4 Y2 Y0 LED| membrane | X5 X7 RSH RAL RAM LSH LAM Y13 Y11 Y9 Y7 Y5 Y3 Y1 GND | connector '----------------------------------------------------------------' 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 TXT Version Attachment 47798 Plus, Component list... Code:
Amiga 500 Keyboard Component List PCB "MITSUMI, MTM-4V-0, PCB A-500, 56 A620A" IC 40pin MOS 6570-036 (keyboard controller, 6500/1 one-chip microcomputer) IC 16pin 74LS123 (dual retriggerable monostable multivibrators) IC 14pin 74LS27 (triple 3-input NOR gates) IC 8pin HA17555 (precision timer, compatible with NE555) Y1 2pin 3.000MHz (ceramic resonator) Q1 3pin C458 C (BC458C, NPN transistor) (Ctrl+Amiga+Amiga) Q2 3pin C458 C (BC458C, NPN transistor) (CAPS LED) R1 2pin 47K Ohm (for Q1 input/pullup) (Ctrl+Amiga+Amiga) R2 2pin 47K Ohm (for HA17555 dis+thr) R3 2pin 1M Ohm (for HA17555 trig) (Ctrl+Amiga+Amiga and power-up) R4 2pin 150 Ohm (for Q2 output/limit) (CAPS LED) R5 2pin 22 Ohm (for DRV GRN LED) R6 2pin 22 Ohm (for PW RED LED) R7 2pin 120K Ohm (for 74LS123 first RC) brown-red-yellow ??? 120K ? R8 2pin 10K Ohm (for 74LS123 second RC) R9 2pin 47K Ohm (for 74LS123 first trigger) R10 2pin 100 Ohm (for Q2 input/limit) (CAPS LED) C1 2pin 1nF (for KCLK signal) C2 2pin 1nF (for KDAT signal) C3 2pin 22uF 16V (for 40pin IC supply) C4 2pin 100nF (for 40pin IC supply) C5 2pin 10uF 16V (for HA17555 dis+thr) C6 2pin 100nF (for HA17555 supply) C7 2pin 100nF (for 74LS123 supply) C8 2pin 100nF (for HA17555 cv) C9 2pin 100nF (for HA17555 trig) (power-up reset?) C10 2pin 1uF 16V (for 74LS123 first RC) C11 2pin 100nF (for 74LS123 second RC) C12 2pin 10pF (for Y1 clock) C13 2pin 10pF (for Y1 clock) C14 2pin not installed (for 40pin IC supply) D 4pin PW RED (power LED) (two diodes in series for "wide" light) D 4pin DRV GREEN (floppy LED) (two diodes in series for "wide" light) FB1 2pin not installed (alternately uses only a simple wire) FB2 2pin not installed (alternately uses only a simple wire) FB3 2pin not installed (alternately uses only a simple wire) FB4 2pin not installed (alternately uses only a simple wire) CN 8pin Connector to Amiga Mainboard CN 31pin Connector to Keyboard Membrane (including CAPS LED) membrane key resistance is 190 ohm |
07 March 2016, 23:27 | #2 |
Global Moderator
Join Date: Aug 2008
Location: Sidcup, England
Posts: 10,300
|
Good work, nocash!
|
23 March 2016, 14:44 | #3 |
AMOS Extensions Developer
Join Date: Jun 2007
Location: near Cambridge, UK
Age: 44
Posts: 1,924
|
Agreed, thanks for sharing
|
29 April 2016, 07:38 | #4 |
Posts: n/a
|
Arrived looking for this exact info, and I found another invaluable work by Nocash, thanks!
|
12 June 2017, 01:56 | #5 |
Posts: n/a
|
The reset handling circuit schematics has 2 errors at least if I compare this schematics with my A500 rev 3 Amiga that is equipped with an early single pcb (no flat cable connector) keyboard made by HiTek.
The 74LS27 port used to check CTRL + C= + A combination press has to be swapped with the one checking for watchdog on /Y15 and the Q1 npn has E and B swapped. Anyway thanks so much to author since this schematics has been precious to debug my dead keyboard. Thanks, wizy |
12 June 2017, 10:04 | #6 |
Amiga Nuts!
Join Date: Sep 2006
Location: Le Mayet d'Ecole, 03800, FRANCE
Posts: 176
|
good work nocash ^^)
btw, the two attachments you list on the first post aren't downloadable, all I get is an error message calling the admin... :-( |
12 June 2017, 10:04 | #7 |
Unregistered User
Join Date: Sep 2012
Location: Copenhagen / DK
Age: 44
Posts: 4,190
|
In my experience, a keyboard from a Rev 3 A500 is not fully compatible with the later revisions motherboards. All the keys work individually, but Ctrl-A-A does not, so they changed something in relation to the reset signal.
|
13 June 2017, 03:21 | #8 | |
Posts: n/a
|
Quote:
As said unvaluable work in any case being the only schematics I could find and made me go on fixing my A500, I just suggest mods so that if someone in my situation will arrive here looking for schematics will start from a correct situation. |
|
05 February 2018, 17:41 | #9 |
Posts: n/a
|
|
06 February 2018, 06:09 | #10 |
old bearded fool
Join Date: Jan 2010
Location: Bangkok
Age: 56
Posts: 779
|
I couldn't find the original image so created a few variants, see attached files.
Linux commands used to convert the ASCII text to images (requires ImageMagick). Black PNG Code:
convert -size 1000x2000 xc:black -font "FreeMono" -pointsize 12 -fill white -annotate +15+15 "@a500_keyboard_mitsumi_schematics.txt" -trim -bordercolor "#000" -border 10 +repage black.png Code:
convert -size 1000x2000 xc:black -font "FreeMono" -pointsize 12 -fill white -annotate +15+15 "@a500_keyboard_mitsumi_schematics.txt" -trim -bordercolor "#000" -border 10 +repage black.gif Code:
convert -size 1000x2000 xc:white -font "FreeMono" -pointsize 12 -fill black -annotate +15+15 "@a500_keyboard_mitsumi_schematics.txt" -trim -bordercolor "#fff" -border 10 +repage white.png Code:
convert -size 1000x2000 xc:white -font "FreeMono" -pointsize 12 -fill black -annotate +15+15 "@a500_keyboard_mitsumi_schematics.txt" -trim -bordercolor "#fff" -border 10 +repage white.gif Last edited by modrobert; 06 February 2018 at 06:38. Reason: Added the commands used to create the images. |
08 February 2018, 15:58 | #11 |
Posts: n/a
|
Oh.. I was hoping for the schematic as a drawing-gif.... not the text as a gif.
As a sidenote, I've recreated this (mostly) in KiCad. PDF is attached. I also have the two-connector version of the keyboard which i need to transcribe next. I'll be putting these up on github, once i'm happy with them. Note: this is not complete. Some of the power caps are not in place, and there are some arrangement issues i have with it right now. Comments, corrections, etc are welcome. @nocash -- btw, thank you! I (and i'm sure others that are reading this) greatly appreciate your work on this... and I appreciate your work on all of your emulation ports I've used. ) Cheers to ya! |
13 February 2018, 15:44 | #12 |
Posts: n/a
|
And here is the repository: https://github.com/BleuLlama/AmigaSchematics
For now it only has the 500 Mitsumi (one edge connector) schematic, but I have the older one with two edge connectors which I'll capture and document at some point. |
29 April 2018, 05:55 | #13 |
Registered User
Join Date: Sep 2009
Location: Syd
Posts: 184
|
Thanks, much appreciated
|
02 March 2020, 13:55 | #14 |
Registered User
Join Date: Dec 2018
Location: UK
Posts: 1,716
|
Thank you to yorgle for the schematics which helped me a lot when putting this together, and for when troubleshooting and fixing my A500 keyboard!
I would have liked the keyboard membrane board layout to be in amigapcb.org and was looking for something similar, but could not find anything. The people with hardware keyboards solutions would already have such a board layout design, but I can't find anything that is available to view and download. So I have created a yEd (https://www.yworks.com/products/yed) diagram of the Mitsumi A619A membrane: The master/source .graphml file can be found at: https://github.com/solarmon/Amiga-Ke...itsumi%20A619A It is best viewed in yEd so that you can select/highlight the links and follow the traces. |
12 April 2020, 21:16 | #15 | |
Code Kitten
Join Date: Aug 2015
Location: Montreal/Canadia
Age: 52
Posts: 1,178
|
For those who may be interested, I have updated the schematics a little bit:
All in all, these are very minor changes the main goal was for the schematics to better match the official Commodore terminology so there is no risk of confusion. I guess it would be nice if this page was integrated to the A500 schematics listed at http://www.amigawiki.org/doku.php?id...ice:schematics. Quote:
My repo is available at https://github.com/nekoniaow/AmigaSchematics but I would encourage anyone to work from yorke's repository though to avoid fragmentation. I do not plan to make any more changes beyond this point. |
|
12 April 2020, 21:54 | #16 |
Registered User
Join Date: Dec 2018
Location: UK
Posts: 1,716
|
@ReadOnlyCat,
I think there is a labelling error on the previous version and it does not seem to be corrected in this new version: On pin 15 of the keyboard MCU you have it labelled as "PC5_Y6" but I believe it should be "PC5_Y5"? |
13 April 2020, 00:57 | #17 | |
Code Kitten
Join Date: Aug 2015
Location: Montreal/Canadia
Age: 52
Posts: 1,178
|
Quote:
I have fixed that and while I was at it renamed the 6570 pins to their proper MOS names and added the usage labels at the wire/pin junctions instead. Also renamed a few symbols to match (https://www.amiga-stuff.com/hardware/6500_1.html) and to those used in corresponding Commodore schematics. It looks like there should be no need for additional changes this time. The Kicad files are still at https://github.com/nekoniaow/AmigaSchematics and I will be creating another pull request to yorge's repository after sending this post. |
|
Currently Active Users Viewing This Thread: 1 (0 members and 1 guests) | |
Thread Tools | |
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
DIY PS/2 keyboard to Amiga 500? | Solo761 | Hardware mods | 39 | 10 December 2020 11:25 |
How to: Convert an A500/A500+ Mitsumi keyboard to an A4000 keyboard. | Turran | Hardware pics | 10 | 15 September 2017 22:46 |
Amiga 500 - keyboard issue | DinoDini | support.Hardware | 3 | 27 January 2016 11:45 |
Amiga 500 keyboard problems | Exl | support.Hardware | 3 | 19 August 2015 21:48 |
Amiga 500 Plus keyboard problems | adgloride | support.Hardware | 12 | 07 July 2004 16:48 |
|
|