Category Archives: Computer

Computer

Programming ATF22V10 PLD – 7 Segment with Linux

The ATF22V10 is a Programmable Logic Device. This means you can program the logic in the chip.

Internally it looks like a big matrix of connections which you can program to connect/disconnect from certain logic.

It has just a bunch of inputs/outputs

So if we want to have a 7 Segment decoder (you can easily buy a BCD decoder .. but these only work for displaying 0-9 and not 0-9A-F for displaying HEX numbers)

7 Segment display
Binary IN7 Segment decodedDisplays
D C B AA B C D E F G
0 0 0 01 1 1 1 1 1 00
0 0 0 10 1 1 0 0 0 0 1
0 0 1 0 1 1 0 1 1 0 12
0 0 1 11 1 1 1 0 0 13
0 1 0 00 1 1 0 0 1 14
0 1 0 11 0 1 1 0 1 15
0 1 1 0 1 0 1 1 1 1 16
0 1 1 1 1 1 1 0 0 0 0 7
1 0 0 01 1 1 1 1 1 18
1 0 0 11 1 1 1 0 1 19
1 0 1 01 1 1 0 1 1 1A
1 0 1 10 0 1 1 1 1 1B
1 1 0 0 1 0 0 1 1 1 0C
1 1 0 10 1 1 1 1 0 1D
1 1 1 01 0 0 1 1 1 1E
1 1 1 11 0 0 0 1 1 1F

Now we see that segment A is 1 in the case of (0,2,3,5,6,7,8,9,A,C,E,F)

When programming the PLD we can write that as: (note / means inverted a plus is OR, and * is AND)
So A is 0 in case of input being (1,4,B,D)

/QA = /D1 * /C1 * /B1 * A1
    + /D1 * C1 * /B1 * /A1
    + D1 * /C1 * B1 * A1
    + D1 * C1 * /B1 * A1

Complete code for galasm

Compiling and burning

GAL22V10
7SEGMENT

Clock   D1   C1   B1   A1    D2   C2    B2    A2    NC  NC   GND
/OE   NC    NC  NC  QG    QF    QE    QD   QC    QB   QA   VCC


/QA =   /D1 * /C1 * /B1 * A1
        + /D1 * C1 * /B1 * /A1
        + D1 * /C1 * B1 * A1
        + D1 * C1 * /B1 * A1

/QB=    /D1 * C1 * /B1 * A1
        + /D1 * C1 * B1 * /A1
        + D1 * /C1 * B1 * A1
        + D1 * C1 * /B1 * /A1
        + D1 * C1 * B1 * /A1
        + D1 * C1 * B1 * A1

/QC =   /D1 * /C1 * B1 * /A1
        + D1 * C1 * /B1 * /A1
        + D1 * C1 * B1 * /A1
        + D1 * C1 * B1 * A1


/QD=      /D1 * /C1* /B1 * A1
        + /D1 * C1 * /B1 * /A1
        + /D1 * C1 * B1 * A1
        + D1 * /C1 * B1 * /A1
        + D1 * C1 * B1 * A1

/QE =     /D1 * /C1 * /B1 * A1
        + /D1 * /C1 * B1 * A1
        + /D1 * C1 * /B1 * /A1
        + /D1 * C1 * /B1 * A1
        + /D1 * C1 * B1 * A1
        + D1 * /C1 * /B1 * A1

/QF =     /D1 * /C1 * /B1 * A1
        + /D1 * /C1 * B1 * /A1
        + /D1 * /C1 * B1 * A1
        + /D1 * C1 * B1 * A1
        + D1 * C1 * /B1 * A1

/QG =     /D1 * /C1 * /B1 * /A1
        + /D1 * /C1 * /B1 * A1
        + /D1 * C1 * B1 * A1
        + D1 * C1 * /B1 * /A1

DESCRIPTION
A 7 segment hex decoder

galasm 7seghex.gal

minipro -p ATF22V10CQZ -w 7seghex.jed

minipro -p ATF22V10CQZ -w 7seghex.jed
Found TL866II+ 04.2.129 (0x281)
Warning: Firmware is newer than expected.
  Expected  04.2.128 (0x280)
  Found     04.2.129 (0x281)

VPP=12V
Warning! JED file doesn't match the selected device!

Declared fuse checksum: 0x98D5 Calculated: 0x98D5 ... OK
Declared file checksum: 0x40B3 Calculated: 0x41A8 ... Mismatch!
JED file parsed OK

Use -P to skip write protect

Erasing... 0.33Sec OK
Writing jedec file...  5.01Sec  OK
Reading device...  0.32Sec  OK
Writing lock bit... 0.35Sec OK
Verification failed at address 0x16C6: File=0x01, Device=0x00 < ------------------ Gives error, but burning seems okay

henri@zspot:~/projects/galasm$ minipro -p ATF22V10CQZ -r 7seghex.out
Found TL866II+ 04.2.129 (0x281)
Warning: Firmware is newer than expected.
  Expected  04.2.128 (0x280)
  Found     04.2.129 (0x281)
Reading device...  0.32Sec  OK

Gives all zeros as output, but device works!
DIP switches are 1100 -> C
Computer

Address decoding with split IO

Made a simulation of my new address decoder.
It uses a 74LS138 and a bunch of NAND gates.
You can safe using 4 NAND gates if you are not going to use split IO

Address
8000-FFFFROMROM
7000-7FFFSound chipSID
6000-6FFFDisplay + cursorVIA1
5000-5FFFKeymatrixVIA2
4800-4FFFsplit ioIO
4000-47FFsplit ioIO – ACIA
0000-3FFFUses clockRAM
Above part is a single chip 74LS138

UPDATE: Found some 74LS139, so i could have changed some things around.

Simplified schematic 74LS139

Try it over here:

https://simulator.io/board/W8sQkHl1We/1

Computer

Eurocards

UPDATE 20240927 PCBs are in

I found some stuff while sorting out some old computer stuff.
Way back, when my Amiga was my main computer, i wanted to make my own version. A modular one.

So i started to segmentize the amiga, to put it on several exchangeable cards.

Eurocards are standardized prints 150mm x 100mm, mostly with a DIN41612 connector.

DIN41612
Eurocard example

When you make modules you can change/upgrade/test, you can have a very easy interchangeable system using a backplane like this

So i started planning those modules:

  • CPU – 68000 but upgradeable to 68030 or alike
  • Memory – With expansion
  • Sound
  • Video
  • More IO possibilities
  • Keyboard (see more at the bottom of this page)

I had a nice case which could hold a big backplane, custom powersupply. And a front panel containing drives, leds and knobs. (I know i have more info on this somewhere on my fileserver)

A nice example picture i found on danceswithferrets website

I never finished this project.
I used Tech Manuals and print layouts to understand how things where done.

Part of schematic

I started to draw the modules like they where placed on the print on semi transparent (chalk)paper, the kind of paper that was used for electronic and mechanic diagrams.

TOP Part of print
Bottom part of print
Both on top of eachother

UPDATE 20240927 PCBs are in

Own designed PCB
Computer

Selling a lot of my computer collection

UPDATE : Bought after selling these

The last days i’ve been selling a lot of my old computers.
They have been in my collection for many years, but now its time to part.
Time for others to enjoy them.

(Instead of posting which ones are being sold and which i’ve still got on this page i’ll make another post)

I started collecting when i studied computer sciences.
It’s a wonder my parents attic wasn’t collapsing.
(They let me store many computers on their attic, let me run a mainframe in the house (previous post) and let me have computer-parties (pre-lan) in their home. (They even left, and gave me the space) .. 15+ teens with computers … there was a pingpong table in the livingroom (besides the other tables in the house ) For all computers.

Then i’ve got even more, when living on my own. (At some point about 140. )

A few years later i got rid of uninteresting computers (to my taste at that time) and incomplete ones. Then i filtered-out the non working.

Still leaving with a lot of computers, i kept these for many years.

Now i only want the ones i’ve worked with, or are special to me.

My first computer was a Commodore Vic-20. Friends had the popular C64. So i kept 2 of both.
In Junior Technical School i’ve used the BBC Acorn a lot (Funny story below)
My then friend Richard had a Atari ST, loads of fun we had with that machine, so i’m keeping a Atari 1040STf.
Another friend used a Apple SE, so that one i also keep for now.
I’ve been programming a lot on 80×86, the first dos PC’s, i’m still looking for a old machine (Laser XT) which i used way back then. But for now i’ve got a Sinclair PC200.
I’ll keep a old Commodore PET 2001, because its cute.
Besides having a cute PET, i’ve got a Holborn System. Made in Holland (Enschede), there are only a few left according to some sites: only 200 made! (Holborn means Holland Born) One of the inventors was from Holten, my birthplace. (Polak)

Putting the system together in 2018

At school we kept a list of everyone’s collection.

Soo .. the story about the BBC Acorn.

When i was at school outside study hours, i went to the computer lab.
This was one classroom with about 16 BBC Acorns and a master (teacher station). When they saw how enthusiastic i was, i got the key to the classroom. I even got access to the master system. And after a little hacking i’ve gained access to the teachers files.
There was a simple network system, i think it was called Econet.
The teachers system was the only one with a disk station.

I liked the ‘highres’ line graphics you could make on the machines. (640×256)
So i’ve wrote a lot of programs using this mode.
I even wrote a program which drew a 3D robotarm on screen using wireframe graphics.
At that time my mathematics scores where .. bad.
Wasn’t interested i think.
But drawing 3D robotic arms are not possible using mathematics, like using sinus, triangulary etcetera.
So when my mathematics teacher saw my program, he didn’t believe me.
So .. fooling around in the computer lab, i missed start of classes. And later on .. worse .. i almost was not allowed to do my final exams.
I was late several times (and one of the first to leave, …. straight from and to the computer lab. )

I’ve got some programs printed on paper, i will use my leftover BBC Acorn (or a emulator) to capture some screen examples.

Sold stuff

UPDATE : Selling a lot, but i’ve bought some others between 2020-2023

  • SDK-85
  • Laser Xt/3
  • 80386 DX

Also a “new” 1084 monitor (CRT for a Commodore 64)
Now i have to look for a VGA Crt to get old vga-register manipulation programs working.

Computer

6502 news

Divers new additions to the 6502 project

Above is my design for a hex keyboard to enter opcodes in hex using a simple monitor program.
i used a 74ls922 which can decode a 4×4 matrix. I’d rather had a 74ls723 which can encode 20 keys.

Nowhere to be found. So i have to think of a new plan.

Now it is configured as follows:

CDEF
89AB
4567
0123

When pressing the alternate key

addr
(to implement)		run
(1/2 implemented)		reset
(to implement)
step instruction
(to implement)
memory next
memory previous
PCB design for matrix hexboard with place for notes

Meanwhile i’ve ordered new keys (the ones i’ve been using for my photomanager project and wnat to have a setup like this:

??addrrunreset
CDEF?
89ABstep
4567mem next
0123mem prev

When you want to show the status of busses and alike, you can’t use a led and restistor directly on the bus, it will require too much current.
So i’ve been using below schematic which uses a darlington array.

Now i can display databus, address bus and i’ve been using this for address decoding logic and hex keyboard.

I’ve implemented a second VIA chip, and ordered components to amplify the SID sound part

Computer

Programming languages

I’ve used a lot of programming languages, and besides that a few scripting languages.

Scripting is used to automate stuff, but probably use other tools under the hood. A programming language can probably do this by itself. Most of the time a programming language needs compiling into a executable form. Whereas a script is directly intepreted at runtime.

I’m not good at programming, but i understand the syntax and can read most of it.
My programming is mostly by example/copy-paste.
Below a list of programming languages and a table below that some scripting languages.

Sooo .. what do i like, still use and why?

Bash is my swiss army knife.
Making Web stuff? – PHP
Iot – C and Javascript
Advanced programming/Longer programs or Machine Learning – Python

And because of recent projects … i have to mention 6502 machinecode!

Programming languages i’ve used

BasicThe first programming language i learned. There are many dialects for many different systems.
PascalI learned to program in school.
Generic pascal and later Turbo Pascal
PLM/86This is relatively unknown programming language. Written for intel processors. It used a lot of ms-dos subroutines. Like dsso which stands for dos-standard-string-out.
dsso(@(‘Print this text’,eos));
And called a dos routine like below
(assembly example)
mov dx,(messageaddress)
mov ah,09h
int 21h
AssemblyStarted with 6502 assemby on my little home computer (a vic-20).
After that i learned to program 8085 assembly in school.
Also learned a little Z80 programming.
When i got a amiga i started with 68000 assembly.
And getting the hang of it, some friends and me started programming 80×86.
CFor a project I needed C programming to control a parallel port, for example for my controllable webcam.
Also recently the microcontrollers like the Arduino’s are programmed in C/C++
PerlPerl was also a interesting language, i bought myself a book and started with the examples.
One of my friends was a Perl wizard, but i could never get the hang of it. Even with his help.
Tcl/TKTCL stands for Tool Command Language, i used the TK extension. So Tcl/TK i used for creating GUI tools in linux. But like what i later used zenity and yad, i think these are more scripting languages.
PHPPHP i used extensively, one of my first big projects was a tunesearch engine with a mysql database.
PythonThe last years i’ve been using python more and more. Python has become the de facto standard for IT.
HaskellWell .. it is a programming language but i only use it to configure my Xmonad desktop.
JavascriptI’ve made a lot of webbased nonsence. PHP/CGI scripts/flash but i also used javascript.
Now i’m primarily using javascript for NodeRed

Scripting languages i’ve used

batDos batch files is a kind of scripting language
KshKorn Shell, i did a workshop ksh because i was a AIX admin.
Didn’t use this much, because you could install the linux toolkit, and could use bash after that.
BashI write a lot of things in bash, this is my preferred tool for fast and easy automation.
When it’s web based i use PHP
LuaI had to write some plugins for my Flightsim Setup

What about Sql, Dbase, Sed, Puredata and blocky those are all on the Programming Lanuages page of Wikipedia???
Well those i find more of a application markup language.
Then you can say abc-music and bmw (bagpipe music writer) are languages also!??

Some call Ansible a programming language, but this is incorrect. It is driven by python scripts and yaml config files.

Below some code part examples of different CPU assembly code

#6502 
    PUSH CX
    PUSH DI
    PUSH SI
    MOV AX,cry
    MOV BX,(2*40)
    MUL BX
    MOV DI,AX
    ADD DI,(2*31)
    MOV SI,adr1
    SUB SI,8       
    MOV CX,8

Z80
    LD H,00H
    LD B,01H
    LD A,(IX+00)
    OUT (01H),A
    LD A,(IY+00)
    OUT (02H),A
    DJNZ LUS3
    LD B,01H
    LD A,(IX+07)
    OUT (01H),A
    LD A,(IY+07)
    OUT (02H),A

#8085
    LDA 2050
    MOV H, A
    LDA 2051
    ADD H
    MOV L, A
    MVI A 00
    ADC A
    MOV H, A
    SHLD 3050
    HLT

#68000
    bsr send
    bsr delay2
    move.w #$38,d0
    bsr send
    bsr delay2
    move.w #$38,d0
    bsr send
    bsr delay2
    move.w #$01,d0
    bsr send
    bsr delay2
    move.w #$0c,d0
    bsr send
    move.w #$06,d0
    bsr send
    rts

#80x68
    mov bx,split
    and bx,1111111111b
    mov dx,3d4h
    mov al,18h
    mov ah,bl
    out dx,ax
    mov bl,bh
    xor bh,bh
    shl bx,1
    mov bx,[bx+offset ormsk]
    mov al,9
    out dx,al
    inc dx
    in al,dx
    and al,10111111b

For assembly i use or used below:
vasm – vasm is a portable and retargetable assembler – which can be used for a lot of different CPUs
masm – a assembler for 80×86, i used this for programming on DOS machines. Also for little projects i used the alway available debug executable.
seka/masterseka – programming 68000 on my amiga

Computer

6502 cont.

UPDATE: 20220823 Sid working

Kicad VIA/PIA tester

Above is my Kicad design (reverse engineering print below, which was made for my 6802CPU, which i could use to test the 6822 PIA)
The 6822 is simular to 6502 in design. So i’m going to redo this for my 6502.
The 7 segment displays are a start of hex-keyboard/display combo i’m going to post more of in the next days.

Below a part of the rom for the LCD dual line display.

Part of the ROM assembly code, top part is text (o.a. japanese)

Started to write routines which i can call to manipulate the display. Setting the pointer to a message, setting the line to use and a subset of controlls like: Center, Right, binary to ascii, scrolling, etcetera 

        lda #0             ; set line number
        sta lineno         ; store
        jsr gotoline       ; goto line in display
        lda #<message      ; get address from message and store for printline subroutine
        sta messagestore
        lda #>message
        sta messagestore+1
        jsr printline      ; print

        lda #1  ; set line number
        sta lineno      ; store
        jsr gotoline
        lda #<message2
        sta messagestore
        lda #>message2
        sta messagestore+1
        jsr printline

Above additions:
New address decoder
Below left the new graphical display, below right a test board which shows address lines and decoded chip-enable lines.

A15 high -> ROM
A15 && A14 low -> RAM
combination of A15 low and A14 high – A13 and A12 wil select peripherals.

Adress decoding
Start of a wirewrapped version

Above is a start of a wirewrapped version, i also started a PCB design in KIcad that will continuously be changed as i alter designs.

UPDATE SID Working! Using new address decoder.

SID = $7000

makesound:
	lda #0
	sta SID+$5 ; Channel1 - attack/decay
	
	lda #250
	sta SID+$6 ; Channel1 - Sustain/Release
	
	lda #$95
	sta SID+$0 ; Channel1 - Frequency low-byte
	
	lda #$44
	sta SID+$1 ; Channel1 - Frequency high-byte

	lda #%00100001
	sta SID+$4 ; SAW + Gate

	lda #$0f
	sta SID+$18 ; Volume max
Computer

C64 Cartridge

Got IC Sockets in today, together with other goodies.

So i soldered the C64 Cartridge print.

Putting a bin on the eeprom

sudo minipro -p AT28C64 -w 8kcart.bin

Welll .. allmost working.
Some strange artifacts, but is running.

The long wire … is a ‘jumper’ .. i cant find ONE (free) jumper in my lab!

Computer

6502 progress

Added second VIA chip. (For hex keyboard)

Skipped the sound setups with simple components or the Yamaha chip. Straight to the commodore SID chip. Added a amplifier and a speaker.

Added ROM functions for line printing. Picture with 2 lines, and my name in Japanese

Now I have to wait for components. I’ve made a simulation for a address decoder.

Rest I’ve put in previous posts as updates.

Meanwhile testing 6502 apps on Android


Computer

Weird things at work

Leave a comment

From a long time ago

(two examples)

There was a place i’ve worked, they did something weird with network masks.
The cause was probably because of changes in the network, and some things had to be re-routed.
When doing routing you use a network mask, this mask is used in tcp/ip routing. When an IP is not in a local network, which boundaries are set by the mask, the protocol will use the gateway to break out of the network.

Example time!

192.168.1.2 – computer IP
192.168.1.0 – network it sees as local
255.255.255.0 – network mask
192.168.1.1 – gateway of example

in binary

11000000.10101000.00000001.00000010 – computer IP
11000000.10101000.00000001.00000000 – network
11111111.11111111.11111111.00000000 – mask (should be al 1’s until the boundary of the network)

The 1’s in the mask should work as a filter!

What i’ve seen was something like a mask
11111111.1111111.00111111.00000000 !
This gave the network a gap into another network!

This is NOT encouraged, don’t do this.
Theoretical and seen in a real live environment .. it CAN work

Another weird one

I was asked to look into a problem at the Johan Cruyff Foundation.
Btw I ran into the guy, but I didn’t know who he was, they had to explain.
(I ‘m not into football)

Some PC’s sometimes could not connect to the network. Sometimes the printer didn’t work.
A colleague of mine looked into it and could not find it.

  • The order in which powered up the PC’s and printer seems to matter.
  • From the 7-8 devices only 6 worked.

So I drove to Amsterdam, turned on a pc, and looked at its network settings.
It was getting a IP, but it was a PUBLIC one!
Looking at another machine, it was also a public one!

The router was locked inside a cabinet, but I knew the famous dutch telecom provider had done something like this! (below)

As it should be (4 ports example)

The organisation had a range of 6 public addresses, thats why not all machines could connect.
These windows pc where connected directly to the internet!
(Some virusscanning required I think!)