68000 SBC, C64 Git and SID Player

Working on 68000 Single Board Computer.

Made a clock circuit and busy designing a power-on-reset schematic. I’ve made one before, but this circuit needs RESET and HALT being pulled low.

8mhz 5V

The 68000 being 24 bit address and 16 bit data needs 2x 8-bit roms and 2x 8 bit ram, but i didn’t have the components yet in this picture.

Address decoder using ATF22V10C is also halfway.
Schematics online soon.

Started a protected Git repo for C64 demo and proof of concepts for our old ICECREW group.

Installed Gitea, behind a reverse proxy.
Part of reverse proxy

ProxyRequests Off
ProxyPreserveHost On
SSLProxyVerify none
SSLProxyCheckPeerCN off
SSLProxyCheckPeerName off

<Location />
ProxyPass   http://10.x.y.z:3000/
ProxyPassReverse  http://10.x.y.z:3000/
Require ip 213.10.144.27
Require ip a.b.c.d
Require ip e.f.g.h
</Location>

Gitea config with token login over https

Generate token
Login https://icecrew.henriaanstoot.nl/

Select your profile (upper right)

And select Settings > Applications

Select a name for your token. And press generate

Top screen shows a token, copy this!

Create new project
Press explore (upper left)

Select organisation and icecrew

Press New Repository, give a name and create

(press https when not defaulted, there is NO ssh to this server)

The example is wrong! (Use below changing TOKENHERE and PROJECTNAME

touch README.md
git init -b master
git add README.md
git commit -m "first commit"
git remote add origin https://TOKENHERE@icecrew.henriaanstoot.nl/icecrew/PROJECTNAME.git
git push -u origin master

Clone a project
Goto a project

press HTTPS when not defaulted to this.

git clone https://icecrew.henriaanstoot.nl/icecrew/borderflag.git 

edit .git/config and add your token to the url ! to push

My Sidplayer as an option to select own collection.
And I’ve made a top list

# Best composers (no order)
Ouwehand_Reyn
Tel_Jeroen
Huelsbeck_Chris
Rowlands_Steve
Hubbard_Rob
Daglish_Ben
Follin_Tim
Gray_Matt
Tjelta_Geir
Mibri (from get in the Van)

# Best tunes (no order)
R-Type.sid
Arkanoid.sid
Bottom.sid
Turbo_Outrun.sid
A_Tune_for_Unity.sid
Ohne_Dich_Rammstein.sid

# Start of own collection (not in above collection)
Abyssus_Ignis_[8580].sid
Catastrophe_[8580].sid
Dumb_Terminal_[8580].sid
Get_in_the_Van_[8580].sid
Getting_in_the_Van_[8580].sid
Supercharger_[8580].sid
Tuna_Guitar_[8580].sid

Investigating syncing effect to Sid music.

I got a great tip from Youth who made the Freakandel demo presented at X2024.

> Setup the loop to play the music

> Copy part of the memory to the screen ($0400) in the same loop to look for memory locations that are used as variables for the music. > Looking at

> Memory where the music is stored

> Zeropage ($00-$ff)

> See if there's some useful changes that coincide with for example drums

> For my own tunes, I use a music routine where I can put event markers in the music itself and react to those from the code. That's >how I synced https://www.micheldebree.nl/posts/big_angry_sprite/

> You could also try reading the SID registers for voice 3 (waveform and ADSR), those are the only ones that are not write-only. > Obviously you can then only react to those changes in voice 3.

I used retrodebugger to see which bytes are changing.
Then I wrote a program which changes the background colour to this value.
I also made a program to use a joystick to see which address have the most interesting effect.
(use up)

     1                                       !to "sidbgnd.prg",cbm
     2                          
     3                                  * = $0801
     4                          			
     5                          sysline:	
     6  0801 0b0801009e323036...        !byte $0b,$08,$01,$00,$9e,$32,$30,$36,$31,$00,$00,$00 ;= SYS 2061
     7                          
     8                                  * = $080d 
     9                          
    10  080d 78                 	sei
    11  080e a960               	lda #<irq
    12  0810 a208               	ldx #>irq
    13  0812 8d1403             	sta $314
    14  0815 8e1503             	stx $315
    15  0818 a91b               	lda #$1b
    16  081a a200               	ldx #$00
    17  081c a07f               	ldy #$7f 
    18  081e 8d11d0             	sta $d011
    19  0821 8e12d0             	stx $d012
    20  0824 8c0ddc             	sty $dc0d
    21  0827 a901               	lda #$01
    22  0829 8d1ad0             	sta $d01a
    23  082c 8d19d0             	sta $d019 
    24  082f a900               	lda #$00
    25  0831 200010             	jsr $1000 
    26  0834 58                 	cli
    27  0835 a920               	lda #$20
    28  0837 8d6b08             	sta vector
    29  083a a917               	lda #$17
    30  083c 8d6c08             	sta vector+1
    31  083f a000               	ldy #$00
    32  0841 b93017             hold 	lda $1730,y
    33  0844 8d20d0             	sta $D020
    34  0847 ad00dc             	lda $dc00
    35  084a 2901               	and #$1
    36  084c c901               	cmp #$1
    37  084e f0f1               	beq hold
    38  0850 ad00dc             	lda $dc00
    39  0853 2901               	and #$1
    40  0855 c900               	cmp #$0
    41  0857 f0e8               	beq hold
    42  0859 c8                 	iny
    43  085a 8c6d08             	sty vector+2
    44  085d 4c4108             	jmp hold 
    45                          irq
    46  0860 a901               	lda #$01
    47  0862 8d19d0             	sta $d019 
    48  0865 200310             	jsr $1003 
    49  0868 4c31ea             	jmp $ea31
    50                          
    51                          vector
    52  086b 0000               	!byte $00,$00
    53                                      
    54                          	* = $1000
    55  1000 4c37104c85104c2f...	!binary "Techno_Drums.sid" ,, $7c+2

Raster line with open borders to draw a flag

A fun experiment using opening the C64 border and changing colors on certain rasterlines.

Screenshot (only a little artefact on the lefthand side)

Code (acme)

acme borderflag.asm
x64 +drive8truedrive borderflag.prg

!cpu 650rasterline
!to "borderflag.prg",cbm


* = $0801
    !byte $0d,$08,$dc,$07,$9e,$20,$34
    !byte $39,$31,$35,$32,$00,$00,$00

* = $c000
        sei                     ; turn off interrupts

        ldx #1                  ; enable raster interrupts
        stx $d01a

        lda #<irq       	; set raster interrupt vector
        ldx #>irq
        sta $0314
        stx $0315

        ldy #$f0                ; set first interrupt rasterline
        sty $d012
        lda $d011               ; reset rasterline hi bit
        and #%01111111
        sta $d011

        asl $d019               ; ack VIC interrupts
        cli

loop_until_doomsday
        jmp loop_until_doomsday

irq
	asl $d019       	; ack irq

	lda #$01		; set screenframe and background
	sta $d020
	lda #$02
	sta $d021

	lda #$38        	; wait for line $38
	cmp $d012       	
	bne *-3

	lda #$02		; set screenframe and background
	sta $d020
	lda #$01
	sta $d021

	lda #$f9        	; wait for line $f9C
	cmp $d012       	; just below border in 25 row mode
	bne *-3

	lda $d011       	; switch to 24 row mode ($d011 bit 3 = 0)
	and #$f7        	; %11110111
	sta $d011

	lda #$fd        	; wait for line $fd
	cmp $d012       	; just below border in 25 row mode
	bne *-3

	lda $d011       	; switch back to 25 row mode ($d011 bit 3 = 1)
	ora #$08        	; %00001000
	sta $d011

	jmp $ea31		; exit irq

No more protected sheets

I needed to get some data from protected sheets.

But I got this on 100+ files:

F that:

Made a script to remove sheet protection and ran this in a loop over all files.
Bye bye protection.

 ./script.sh /mnt/fileserver/sensordata001.xlsx
Parsing /mnt/fileserver/sensordata001.xlsx
Archive:  this.zip
  inflating: tmp/[Content_Types].xml
  inflating: tmp/_rels/.rels
  inflating: tmp/xl/_rels/workbook.xml.rels
  inflating: tmp/xl/workbook.xml
  inflating: tmp/xl/worksheets/sheet4.xml
  inflating: tmp/xl/worksheets/sheet2.xml
  inflating: tmp/xl/worksheets/sheet3.xml
  inflating: tmp/xl/worksheets/sheet1.xml
  inflating: tmp/xl/styles.xml
  inflating: tmp/xl/theme/theme1.xml
  inflating: tmp/xl/sharedStrings.xml
  inflating: tmp/docProps/core.xml
  inflating: tmp/docProps/app.xml
  adding: [Content_Types].xml (deflated 78%)
  adding: docProps/ (stored 0%)
  adding: docProps/core.xml (deflated 49%)
  adding: docProps/app.xml (deflated 54%)
  adding: _rels/ (stored 0%)
  adding: _rels/.rels (deflated 60%)
  adding: xl/ (stored 0%)
  adding: xl/worksheets/ (stored 0%)
  adding: xl/worksheets/sheet2.xml (deflated 92%)
  adding: xl/worksheets/sheet1.xml (deflated 46%)
  adding: xl/worksheets/sheet4.xml (deflated 92%)
  adding: xl/worksheets/sheet3.xml (deflated 92%)
  adding: xl/_rels/ (stored 0%)
  adding: xl/_rels/workbook.xml.rels (deflated 77%)
  adding: xl/workbook.xml (deflated 56%)
  adding: xl/theme/ (stored 0%)
  adding: xl/theme/theme1.xml (deflated 78%)
  adding: xl/styles.xml (deflated 57%)
  adding: xl/sharedStrings.xml (deflated 23%)

Bash script:
It leaves the original intact, but makes a unprotected copy named the same with unprot_ in front of it.

#!/bin/bash
if [ -n "$1" ]; then
  echo "Parsing $1"
else
  echo "usage : scriptname /path/to/sheet.xlsx"
  exit 0
fi
name=$(basename $1)
dir=$(dirname $1)
rm -f this.zip
rm -rf tmp
mkdir tmp
cp "$1" this.zip
unzip this.zip -d tmp
find tmp/xl/worksheets/ -iname *xml -exec sed -i -e "s/<sheetProtection.*\/>//g" {} \;
cd tmp
rm -f "$dir/unprot_${name}"
zip -r "$dir/unprot_${name}" *
cd ..

Amiga and DIY 68000 single board computer.

Started working on my breadboard version of a 68k computer.
When it’s working, I’ll make a PCB version.
Using almost only parts I still have. (No 8mhz crystal)

The 68000 being 24 bit address and 16 bit data needs 2x 8-bit roms and 2x 8 bit ram, but i didn’t have the components yet in this picture.

While tinkering with above, my Fatter Agnus chip came in.

To make a 1mb chipmem version of your rev 5 amiga (PAL)

You need to have a newer version of the Agnus chip (I had 8371, and bought a 8372a) AND you need a 512kb trapdoor memory expansion.

An unmodded rev 5 will see 512kb Chip mem and 512 Fast mem.

Replacing the Agnus 8371 for 8372a:
I lost my PLCC puller, so I modded a paperclip into a puller 🙂

When placing the new chip, I had to tape pin 41 for PAL version.
I used Polyimide Film tape.

Next I had to cut the jumper 2 connection and solder the other pads.
(Bottom and middle disconnect and middle and top bridged)

Next was another cut on the PCB, this disables the trapdoor card detection.

Success!

Notes for next projects I made using our short holiday in Madeira.

I think we’ve seen Maderia .. 🙂

I bought a little notebook while being there.
I wrote about 12 pages of ideas, schematics and projects to start.

  1. Rewrite Wozmon to use my composite pcb (Atmega328)
    access though via
  2. Building a 68000 pcb with a minimal machine code monitor.
    Using a atf22v10 as address decoder.
    (Same as my 6502 , I love those devices)
    Maybe I’ll add a micro sdcard reader
  3. Add a lcd matrix display to my 8088/8086
  4. Creating a PLA alternative for C64 using ath22v10 (again)
  5. Make backplanes for my 6502, so I can plug cards with different POC cards.
    Clockcard, Latched bus leds, multiple VIA’s, IRQ controller, SID + Buzzer (Maybe also AY-3-8910, see other posts), LCD, composite, serial, Matrix and serial_usb) keyboard)
  6. IRQ controller because I have some devices without opendrain, so I can’t tie all IRQ’s together
  7. Amiga Chip Mem mod for rev 5 (using a ‘new’ 8372A)
  8. 8085 Cartridge new approach
  9. C64Pico fix and add backplane + breadboard version for POCs
  10. … more
First version PLA with atf22v10
PCB mockup (two ATF22v10 on top and a wide pin setup for placement in C64
Wide PLA

8085 Cartridge revisited

Working on 8085 cartridge

Problem with cartridge: prg is 17k, exomized 10k.
So you need 2 banks of 8k.
This disables basic rom, needed for the program.
The program needs to be relocated to 0x800 anyway.
So my exomizer options will take care of that.
But the basic is not being enabled again.

exomizer sfx sys -o data.exo -Di_ram_enter=\$37 -Di_ram_during=\$34 -f'LDA #$37 STA $01' 8085.prg 
xa frame.asm -o frame.bin
x64 -cart16 frame.bin 

Result … JAM

68000 Build environment

For my new SBC I’ll need a machine code build environment.

This is what I’ve setup now.

My main workstation is Linux based. While this setup is Linux based, vasm should work on other operating systems also.

Getting and compiling vasm for 68k

wget http://sun.hasenbraten.de/vasm/release/vasm.tar.gz
tar xzvf vasm.tar.gz
cd vasm
# Building
make CPU=m68k SYNTAX=oldstyle
# Using
./vasmm68k_oldstyle -m68000 -Fbin -dotdir -no-opt source.asm
# this generates a.out

# Dumping the file (byte separated and with a offset of 0x8000)
xxd -g 1 -o 0x8000 a.out | head
00008000: 30 3c aa aa 4e f9 00 00 80 04 00 00 00 00 00 00  0<..N...........
00008010: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
00008020: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
00008030: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
00008040: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
00008050: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
00008060: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
00008070: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
00008080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
00008090: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................

# But my 68k needs an ODD EVEN eeprom 
# so I used another tool - romsplit
git clone https://github.com/ullman/romsplit
cd romsplit
make all
# Using romsplit
./romsplit -s a.out odd.rom even.rom
# Split into 4? Split the splits using above
# Output
xxd -g 1 -o 0x8000 odd | head -1 ; xxd -g 1 -o 0x8000 even | head -1
00008000: 30 aa 4e 00 80 00 00 00 00 00 00 00 00 00 00 00  0.N.............
00008000: 3c aa f9 00 04 00 00 00 00 00 00 00 00 00 00 00  <...............
# Burn these with minipro

Disassemble

m68k-linux-gnu-objdump --disassemble-all --target=binary --architecture=m68k a.out

68030 example for friend

# Compile vasm with
make CPU=m68k SYNTAX=mot
------------
vasmm68k_mot  -Fbin  ./edk.asm
-------------
.68030

	ORG $0

*****
* exception table (256 x 4 bytes)
*****
	dc.l $400	; Program Counter na reset (startadres)
	dc.l $20000	; stackpointer (ram locatie)
	dc.l 0,0,0,0,0,0,0,0,0,0,0,0,0,0

	dc.l 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
	dc.l 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
	dc.l 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
	dc.l 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
	dc.l 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
	dc.l 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
	dc.l 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
	dc.l 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
	dc.l 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
	dc.l 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
	dc.l 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
	dc.l 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
	dc.l 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
	dc.l 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
	dc.l 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0

	org $400	; hier starten
	move.l #$0,d0
loop1:
	add.l #$1,d0
	cmp.l #$10000,d0
	bne loop1

	move.l #$0,d0
loop2:
	add.l #$1,d0
	cmp.l #$10000,d0
	bne loop2

	nop
	nop
	nop
-----
vasm 1.9f (c) in 2002-2023 Volker Barthelmann
vasm M68k/CPU32/ColdFire cpu backend 2.6c (c) 2002-2023 Frank Wille
vasm motorola syntax module 3.18 (c) 2002-2023 Frank Wille
vasm binary output module 2.3a (c) 2002-2023 Volker Barthelmann and Frank Wille

org0001:0(acrwx1):	           0 bytes
org0002:0(acrwx1):	        1024 bytes
org0003:400(acrwx2):	          30 bytes
-----
-rw-rw-r--  1 henri    henri       1054 aug 27 11:45  a.out

Movie props and reusing stuff

Follow-up on previous post.

I’ve posted about sounds before, annoying!

The Wilhelm scream is a stock sound effect that has been used in many films and TV series, beginning in 1951 with the film Distant Drums. The scream is usually used when someone is shot, falls from a great height, or is thrown from an explosion. See also Squeaky door.

About movie props

Not that annoying, but I can’t think about anything else as the previous film I saw the prop in.

Props in They Live (1988) I saw in 2024

Wait a minute! Thats from Ghostbusters (1984)

Even another film exists using the same prop (never seen this movie)

The prop was made using a shoe polisher thingy b.t.w.

Playing an old game

While I’m not really a gamer, I played a very old game I loved playing on my Amiga.

Its Ports of Call.

Are there others like this game?

Ports of Call is a 1986 business simulation game developed by German duo Rolf-Dieter Klein and Martin Ulrich, and published by Aegis Interactive Entertainment.
The game simulates the management of a global freight transport company, where the player charters freight, and, using the accumulated profit, can buy more and better ships. Minigames include manually piloting your ship into a specified berth in the harbour and picking up survivors from a life-raft. 

I loved the manoeuvring part, especially the large ships with both front and back rudders.

Here are some screenshots from Amiga Forever emulator

Post about other old games:

"If something is worth doing, it's worth overdoing."