Commodore ARM2SID User manual
ARM2SID quick installation guide
Thank you for your purchase!
ARM2SID is a new replacement for 2 Commodore SID music chips and more.
ARM2SID is a bigger brother of our well known ARMSID, which is a real "plug
& play solution and fully replaces both the MOS6581 and MOS8580 chips.
ARM2SID comes whenever 2 SID chips are needed, usually for stereo. If you
have 2 SID sockets, just place the ARM2SID in the primary socket, SID2 in the
secondary socket, connect both of them with the provided 5 or 10 cm cable,
configure with the provided C64/C128 utility and go.
If you have just one socket and are not afraid of soldering, you can get even
more. Use the provided connector cable, connect the 6 wires to your
C64/C128 and you get the 2nd SID for stereo, the 3rd SID for 3SID music and
OPL FM synthesis compatible with FM Sound Expander!
Enjoy your ARM2SID!
CAUTION: Before you install ARM2SID, the computer must be turned OFF
and disconnected from the power supply.
WARNING: The installation of ARM2SID should be performed by a skilled
person. It requires you to open your Commodore computer. Most of the
chips are sensitive to static electricity, ground yourself. Neither ARTAX nor
NOBOMI will be responsible for any damages caused by an improper
ARM2SID installation.
ARM2SID orientation.
It is very important to place your ARM2SID into the socket the correct way.
The original SID chip has a slightly beveled notch near the pin 1. ARM2SID
has a white printed notch on the PCB above the pin 1. See the pictures from
the Commodore C64:
CAUTION: Please, really DO take care about the ARM2SID orientation. If
you turn the ARM2SID the wrong way, you WILL damage your computer.
High voltage (9 or 12 V) will go to your computer bus and most likely
destroy your computer RAM, ROM and more chips.
The orientation in the Commodore C128 is similar. Always place ARM2SID
with the same orientation as the original SID chip.
NOTCH
Pin 1
Pin 1
printed
NOTCH
NOTCH
printed
NOTCH
Pin 1
Pin 1
Dual socket configuration
This is easy no-soldering solution for stereo SID expanders (MixSID, SIDFX,
SID2SID etc.) or dual-SID boards.
Install the ARM2SID in the primary socket, SID2 in the secondary socket and
connect them with the provided 5 or 10 cm cable. Take care for the proper
ARM2SID and SID2 orientation! Wrong orientation will destroy your
computer!
Configure ARM2SID with the provided ARMSID TESTER utility. Start it,
choose $D400 SID, select M for ADDRESS MAPPING CONFIGURATION and
select PIN CONNECTION: SOCKET, then choose what to play in the LEFT and
RIGHT socket. If your socket supports $DFxx addressing, you can use SFX
(FM) too.
Dual socket configuration for C64 Reloaded MK2
The special ARM2SID version for C64 Reloaded MK2 allows correct
autodetection in this computer. This option however affects the Digifix
introduced in newer ARMSID firmware versions.
Fortunately the Digifix can be set by hardware pin or the software. The
hardware is affected and will set your Digifix to -100%, so for the ARM2SID
usage in C64 Reloaded MK2 you have to change the Digifix configuration to
Software to enjoy the SID music the best. Adjust the Digifix value to desired
level then.
Remember to save the settings to flash memory by pressing ‘P’ key.
Ultimate 64 usage and configuration
Install the ARM2SID in the primary (lower, SID-1) socket and SID2 in the
secondary (upper, SID-2) socket in your Ultimate 64. Connect ARM2SID and
SID2 with the provided special cable harness for Ultimate 64. The small
connector with all pins populated belongs to ARM2SID and the connector
with only 5 pins populated to SID2. The one longer wire connects to left pin
on SID A[5..9] dual pin header in Ultimate 64.
Take care for the proper ARM2SID and SID2 orientation! Wrong orientation
could damage your computer!
The SID A[5..9] brings an addition address line to the ARM2SID to recognize
more different addresses where internal SIDs/SFX could be positioned. It is
controlled by Ext DualSID Range Split setting of Ultimate 64 configuration.
There are some setting common for all ARM2SID modes and then you have
to configure Ultimate 64 and ARM2SID with its configuration utility for
required mode of operation:
•Standard 2 SID stereo
•3 SIDs
•SID + SFX Sound Expander
•SFX Sound Expander only
Common Ultimate 64 settings for ARM2SID usage
You have to enable both SID sockets and disable UltiSID.
U64: SID Socket 1 ... Enabled
U64: SID Socket 2 ... Enabled
U64: UltiSID 1 Address ... Unmapped
U64: UltiSID 2 Address ... Unmapped
It is also necessary to disable Ultimate 64 SID Player Autoconfiguration. The
Ultimate 64 can configure ARMSID using public API and it will modify your
settings unintentionally, the way you did not want it and you could be
confused what is going on, so it is definitely better to disable the
Autoconfiguration and to all configuration yourself. Also disable the UltiSID.
SID Player Autoconfig … Disabled
Allow Autoconfig uses UltiSid … Off
It also a good idea to slightly adjust the Audio Mixer, but this is about
preference of different people. We usually slightly increase the volume of
both sockets and extend the pan for both sockets to wider stereo
enjoyment.
The next screen is ARM2SID test and configuration utility. You will need to
make ARM2SID configuration changes to use different modes. You can also
use it to change between 6581 and 8580 emulation, adjust Digifix and more.
You can download it with the newest firmware from Downloads section on
Retrocomp e-shop or from the author’s pages:
https://www.nobomi.cz/8bit/arm2sid/
Standard 2 SID stereo (SIDs on addresses $D400 and $D420)
Adjust SID Addressing in Ultimate 64 configuration
U64: SID Socket 1 Address ... $D400
U64: SID Socket 2 Address ... $D420
U64: Ext DualSID Range Split ... A8
Configure ARM2SID using ARM2SID Test and Configuration Utility
ARM2SID: PIN CONNECTIONS ... SOCKET
ARM2SID: SID/1 ... SIDL
ARM2SID: SID/2 ... SIDR
ARM2SID: EMULATION MODE ... SID
3 SIDs (SIDs on addresses $D400, $D420 and $D500)
Adjust SID Addressing in Ultimate 64 configuration
U64: SID Socket 1 Address ... $D400
U64: SID Socket 2 Address ... $D420
U64: Ext DualSID Range Split ... A8
Configure ARM2SID using ARM2SID Test and Configuration Utility
ARM2SID: PIN CONNECTIONS ... WIRE
ARM2SID: $D400 ... SIDL
ARM2SID: $D420 ... SID3
ARM2SID: $D500 ... SID3
ARM2SID: $D520 ... SIDL
ARM2SID: $DE00 ... SIDR
ARM2SID: EMULATION MODE ... 3SID
SID + SFX Sound Expander (SID on address $D400, SFX on addresses $DFxx)
Adjust SID Addressing in Ultimate 64 configuration
U64: SID Socket 1 Address ... $D400
U64: SID Socket 2 Address ... $DF40
U64: Ext DualSID Range Split ... A5
Configure ARM2SID using ARM2SID Test and Configuration Utility
ARM2SID: PIN CONNECTIONS ... SOCKET
ARM2SID: SID/1 ... SIDL
ARM2SID: SID/2 ... SFX
ARM2SID: EMULATION MODE ... BOTH
SFX Sound Expander only (SFX on addresses $DFxx)
Using ARM2SID in “SFX only” mode allows the CPU to put all the power to
FM synthesis and so it makes slightly better sound quality.
Adjust SID Addressing in Ultimate 64 configuration
U64: SID Socket 1 Address ... $D400
U64: SID Socket 2 Address ... $DF40
U64: Ext DualSID Range Split ... A5
Configure ARM2SID using ARM2SID Test and Configuration Utility
ARM2SID: PIN CONNECTIONS ... SOCKET
ARM2SID: SID/2 ... SFX
ARM2SID: EMULATION MODE ... SFX
Single socket (wired) configuration
Congratulations, you are the brave one, not afraid of a soldering iron!
Install ARM2SID to the socket with the correct orientation. Connect the
provided cable with the connector to the ARM2SID and connect its wires to
the following points in you C64/C128:
A8 –pin 15 of CPU
A5 –pin 12 of CPU
R/W –pin 5 of expansion port connector
IO –connects to IO2 (pin 10 of expansion port connector) for Sound
Expander SFX $DFxx compatibility, IO1 (pin 7 of expansion port connector)
for $DE00 stereo SID play or both with diodes and resistor pullup.
GND –computer ground, not needed to connect
Audio R –right audio channel, usually connects to pin 7 of A/V DIN jack. We
suggest to add 10µF/10V electrolytic capacitor between ARM2SID Audio R
output and pin 7 of A/V DIN jack to separate the DC component from the
ARM2SID audio output. Capacitor + pin should go to the ARM2SID.
ARM2SID wires connection:
ARM2SID IO connection with diodes:
The ARM2SID IO connection with diodes and a pullup resistor (all parts are
provided with ARM2SID with 30 cm cable wires) is necessary only if you
want to use all possibilities of ARM2SID. In case, that you do not want to use
the 2nd SID on an address $DExx, you do not have to connect IO1 and just
connect the ARM2SID IO pin directly to the IO2 of expansion connector for
the SFX Sound Expander $DFxx. If you do not want to use ARM2SID on
address $DExx and $DFxx, you do not have to connect ARM2SID IO pin at all.
$D5xx addresses decoding in Commodore C128
Using $D5xx addresses in C128 is a little bit difficult because the SIDs chip-
select pin in C128 addresses only $D400-$D4FF range, unlike C64 where it is
$D400-$D7FF. You still need to connect the A8 address pin to the CPU, but
you have to somehow extend the address range of the SIDs chip-select. It is
more complicated, you can not extend the range for C128 mode, you can do
it only for C64 mode where the range of $D5xx addresses is usable (free).
The address decoding of IO peripherals is managed inside C128 by IC
74LS138 named U3. Probably the best way (fastest in signal timing) is a
solution also recommended in the MixSID project by replacing this IC with a
GAL with such a functionality. Described here:
https://github.com/hbekel/MixSID/tree/master/firmware/c128
But if you do not like cutting pins on the board as we do not like, NOBOMI
created a piggy back solution for U3 with 74HCT541. This uses a little bit of
“force” to push the signal where we want to, but all is in the working range
of participating ICs.
Shorten all pins on 74HCT541 with the exception of pins 10 and 17. Wire
(solder) together all pins 2-10 and 11-18. Piggy back place 74HCT541 on top
of U3 and solder the pin 10 of 74HCT541 to the pin 8 of U3. Then solder the
pin 17 of 74HCT541 to the pin 15 of U3. Connect VCC (the pin 20 of
74HCT541 to the pin 16 of U3) and connect G2 (the pin 19 of 74HCT541 to
the pin 14 of U3) by short wires. Finally connect 64/128 signal from the
MMU pin 47 to the pin 1 of 74HCT541.
Single socket (wired) software configuration
If you connected everything as noted before, you can use all configuration
possibilities. If you did not connect some signals, the configuration utility will
allow you to setup everything, but some parts of emulation will not work, it
is up to you, if you need it and connect all the wires.
Configuration for most common stereo or 3 SID music:
If you set stereo and play one SID music, ARM2SID will automatically switch
to dual mono (same music on both audio channels) after 15 seconds of
inactivity on the 2nd channel. This function does not work in 3 SID setup. If
you want dual mono, you have to switch the down-mix in config utility.
Configuration for SFX (Sound Expander compatible):
With this configuration you can play all OPL FM synth music for Sound
Expander and one SID together. You can down-mix to mono, if you do not
use stereo output on your C64. It is possible to switch to SFX only mode
(without SID). In that case all computing power is put to the FM synthesis
and SFX emulation is even better and goes to both channels.
For SFX music it is necessary to the connect ARM2SID IO pin to the pin 10 of
C64/C128 expansion port connector (IO2) to enable $DFxx addressing. You
can connect it directly or with diodes as stated before.
All settings will take effects in emulation only after saving it by key S to RAM
or by key P to save to permanent flash memory. Always save first to the
RAM (press S) and test your configuration before saving it permanent. If you
save to RAM, you can easily return to previous settings by switching
computer off and on again. If configuration works, then save permanently to
the flash memory.
Firmware update
Start firmware update utility and follow the instructions. If the update fails
in some rare circumstances, try to use the blind version of the update utility
(the filename ends with the letter b).
Do not try to update ARM2SID with any ARM hardware programmer
directly. The firmware is encrypted and needs a special bootloader. If you
erase the bootloader, there is no way you can program the ARM2SID with
the correct firmware again and you will need to send it back to us.
More information and support
You can find more information, download the configuration and the
firmware update utility on the author’s website:
https://www.nobomi.cz/8bit/arm2sid/index_en.php
The configuration utility, some SID music, recorded music samples and more
can be downloaded from our ARM2SID e-shop page:
https://retrocomp.cz/produkt?id=20
News, information and discussions on our Faceboook page:
https://www.facebook.com/SIDreplacement/
In case of any troubles, you can get support on the following e-mail:
