• 1: Power Suply Cooling Fan.
  
• 2: Mouse Port.
  
• 3: Keyboard Port.
  
• 4: Audio out. (red=left white=right)
  
• 5: Disk Drive. (Amiga compatiable)
  
• 6: Serial Port. (33.6 Kb 25 Pin)
  
• 7: parallel Port.
  
• 8: RGB Video port. (Amiga compatiable)
  
• 9: Power input. (Standard "kettle" lead)
  
• 10: Midi ports. (In and Out)
  
• 11: CDTV Expansion Slot.
  
• 12: CDTV Video Slot & CD1301 Genlock.

Keyboard Port
Yep, you guessed it, This is where you plug your CDTV keyboard in.
Commodore used the same actual keyboard in the Amiga 3000, 4000 and CDTV but just changed the cable, If you have a dead CDTV keyboard you can take the PCB with all the keys out of an A3000 or 4000 case and put it in the CDTV`s case (Connected to the CDTV using the CDTV`s cable) and it will work, infact Commodore did this in smaller countrys as a cost cutting exersise so you will see original CDTv keyboards with white keys occationally.

• Pin 1: Gnd (Ground)
• Pin 2: kbdata (Data Input)
• Pin 3: kbclock (Keyboard Clock)
• Pin 4: Vcc (+5V Power)
• Pin 5: KBSE (When low, Keyboard Sence)

Audio Out.
This is the main audio out from the CDTV, The connectors are "phono" as used is most stereo systems, There is a left (red) and right (white) connector because the CDTV has a stereo sound card.
The CDTV`s built in CD-Rom is mixed with the CDTV`s before it is sent to the audio out.
The volume control (Through the front display or remote control) does not effect this audio out. (Only the audio jack on the front, Under the power button)

This audio out required a speaker with a built in amplifier. (All stereo systems do this as normal as does most PC speakers and Amiga monitors)

External Disk Drive Port.
This port lets you add up to three external diskdrives to the CDTV, These disk drives are normally 880Kb double density drives but there are special (half speed) 1.74Meg disk drives available.
Power is suplied to the diskdrives by the CDTV and all software configuration is done by the CDTV.
The first disk drive is mounted as DF0, The second is DF1 and so on.
The CDTV will boot of a suitable disk placed in DF0 (The first diskdrive) if there is no CDTV CD in the CD-Rom drive, If a CDTV title is present it will boot of that. If there is an audio Cd in the CD-Rom drive and a suitable floppy disk in the diskdrive then the floppy disk will load. Only if no other bootable drive is found will the audio Cd player load.
With a diskdrive added to the CDTV you can play most 1 Meg Amiga 500 games. (A switch can be added to the CDTV to free up extra memory to play all 1 Meg amiga 500 gamesif required)

• Pin 1: RDY (Disk Ready When Low)
• Pin 2: DKRD (Disk Ready Data)
• Pin 3-7: GND (ground)
• Pin 8: MTRXD (Disk Motor Control When Low)
• Pin 9: SEL3B (Select Drive 3 when low)
• Pin 10: DRESB (Disk Reset when low)
• Pin 11: CHNG (Disk Has Been Removed From Drive - Latched Low)
• Pin 12: +5V (+5 Volts DC)
• Pin 13: SIDEB (Select Disk Side- 0=Upper, 1=Lower)
• Pin 14: WPRO (Disk Is Write Protected When Low)
• Pin 15: TK0 (Drive Head Position Over Track 0 When Low)
• Pin 16: DKWE (Disk Write Enable When Low)
• Pin 17: DKWD (Disk Write Data When Low)
• Pin 18: STEPB (Step The Head-Pulse, First Low, Then High)
• Pin 19: DIRB (Select Head Direction- 0=Innter, 1=Outer)
• Pin 20: SEL1B (Select Drive 1 When Low)
• Pin 21: SEL2B (Select Drive 2 When Low)
• Pin 22: INDEX (Disk Index Pulse When Low)
• Pin 23: +12V (+12 Volts DC)

Serial Port (DC25 Male)
The CDTV uses the same serial port found on all Amiga`s and most PC`s made in 1991.
An adapter can be purchaced from all good computer shops to change it to the 9 pin veriaty on most modern computers.
The serial port is fully compatiable with the PC standard and connecting items like modems, printers and digital camera`s.
The logo underneath the serial port is ment to represent a modem (Its a telephone with data being transmited over it) as this was and still is the most common use of the serial port.
Expect speeds of around 33.6Kb in normal operation.
The serial port complies to the RS232 standard.

Parallel Port. (DB25 Female)
The Parallel port is one of the most used ports for adding upgrades to your CDTV. Printers, Scanners, Sound Capture cards, Video capture cards, networking and even Mp3 Decoder cards can be connected to this single port, The CDTV can use all devices that can connect to a standard Amiga`s parallel port.

Amiga R.G.B. Video port
All Amiga`s have a standard 23 pin video port, including the Commodore CDTV.
There are a selection of cables and cards which connect to this slot from a simple cable to connect it to any TV set with a Scart connector to a scan doubler card which will let you use standard PC monitors.
One of the more unusual expansions which use this port is the Graffito graphics card, It plugs in to the external port and gives you up to 256 colours on supported programs, It is a graphics card which connects to another graphics cards output.

Power Input (110V & 220/240V)
This is the standard power connector found on all modern PC`s and big box Amiga`s, This connector is found on NTSC and PAL CDTV`s.

At socket.

Midi ports (In & out)
These two ports are used by certain electronic instruments but mostly electronic keyboards, It is used to send data either to or from (or both) the computer, This lets you compose music and save it on to the computer as well as alter or make a tune on the computer and download it back to the instrument for playback.
There are also CD+MIDI music CD`s which let you play along with the song with on screen promts.

At socket.

Expansion slot
This slot is sometimes refered to as the SCSI slot, It is the main external expansion slot on the CDTV.
The only type of available card for this slot is an SCSI card but there were plans (And prototypes?) for a 2.5Mb Arcnet card.