Hardware Hacking

All odd pins are grounds, except for pin 25, which is unused.

Pin 2: *Data 0
Pin 4: *Data 1
Pin 6: *Data 2
Pin 8: *Data 3
Pin 10: *Data 4
Pin 12: *Data 5
Pin 14: *Data 6
Pin 16: *Data 7
Pin 18: *Parity
Pin 20: Ground
Pin 22: Ground
Pin 24: Ground
Pin 26: Terminator Power
Pin 28: Ground
Pin 30: Ground
Pin 32: *ATN
Pin 34: Ground (Unused?)
Pin 36: *BSY
Pin 38: *ACK
Pin 40: *RST
Pin 42: *MSG
Pin 44: *SEL
Pin 46: *C/D
Pin 48: *REQ
Pin 50: *I/O

External Floppy Port (DB23 Female)

Pin 1: *Disk Ready
Pin 2: *Disk Read Data
Pin 3: Ground
Pin 4: Ground
Pin 5: Ground
Pin 6: Ground
Pin 7: Ground
Pin 8: *Disk Motor Control
Pin 9: *Select Drive 3
Pin 10: *Disk Reset
Pin 11: *Disk Change (Latched Low)
Pin 12: +5V (250 mA maximum.)
Pin 13: *Select Disk Side (0=Upper, 1=Lower)
Pin 14: *Write Protect
Pin 15: *Track Zero
Pin 16: *Disk Write Enable
Pin 17: *Disk Write Data
Pin 18: *Step (Pulse: Low, then high.)
Pin 19: Direction (0=Inner, 1=Outer)
Pin 20: Unused
Pin 21: *Select Drive 2
Pin 22: *Disk Index Pulse
Pin 23: +12V (160 mA maximum, 540 mA surge.)

Internal Floppy Connector (34-Pin Male Header)

Pin 1: Ground
Pin 2: *Change
Pin 3: Unused
Pin 4: *In Use 1
Pin 5: Ground
Pin 6: *In Use 0
Pin 7: Ground
Pin 8: *Index
Pin 9: Ground
Pin 10: *Select 0
Pin 11: Ground
Pin 12: *Select 1
Pin 13: Ground
Pin 14: Unused
Pin 15: Ground
Pin 16: *MTRI
Pin 17: Ground
Pin 18: Direction
Pin 19: Ground
Pin 20: *Step
Pin 21: Ground
Pin 22: *DKWD
Pin 23: Ground
Pin 24: DKWE (Write Enable?)
Pin 25: Ground
Pin 26: *TRKD
Pin 27: Ground
Pin 28: *Write Protect
Pin 29: Ground
Pin 30: *DKRD
Pin 31: Ground
Pin 32: *Side
Pin 33: Ground
Pin 34: *Ready

Note: some 3.5-inch drives may use different pins for the *Change (diskchange) signal.

PIN# - SIGNAL
1 TX1+
2 TX1-
3 SHLD1
4 SHLDC
5 TXC+
6 TXC-
7 GND
8 +5V
9 NC
10 NC
11 TX2+
12 TX2-
13 SHLD2
14 SHLD0
15 TX0+
16 TX0-
17 NC
18 HPD
19 DDC_DAT
20 DDC_CLK

PIN# - SIGNAL

1 T.M.D.S DATA 2+
2 T.M.D.S DATA 2-
3 T.M.D.S DATA 2 RTN
4 SYNC RTN
5 HORIZ. SYNC TTL
6 VERT. SYNC TTL
7 T.M.D.S CLOCK RTN
8 CHARGING PWR INPUT+
9 1394 PAIR A, DATA
10 1394 PAIR A, DATA+
11 T.M.D.S DATA 1+
12 T.M.D.S DATA 1-
13 T.M.D.S. DATA 1 RTN
14 T.M.D.S CLOCK+
15 T.M.D.S CLOCK-
16 USB DATA+
17 USB DATA-
18 1394 SHIELD/CHARGING POWER INPUT-
19 1394 VG
20 1394 VP
21 T.M.D.S DATA 0-
22 T.M.D.S DATA 0+
23 T.M.D.S DATA 0 RTN
24 STEREO SYNC TTL
25 DDC RTN
26 DDC DATA SDA
27 DDC CLOCK SCL
28 +5 VDC
29 1394 PAIR B, CLOCK+
30 1394 PAIR B, CLOCK-
C1 RED VIDEO OUT
C2 GRN VIDEO OUT
C3 PX CLOCK OUT
C4 BLU VIDEO OUT
C5 COMMON GND RTN