Connector:2nd disc drive (CPC664, CPC6128, CPC6128+)
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CPC664/CPC6128
The following table lists the signal on the "2nd Disk Drive" connector on the back of the CPC664/CPC6128 Signal names in simple brackets show the meaning the signal has today. For your convenience, the pin no. are given as specified in the Shugart standard first, followed by the pin no. as assigned by Amstrad and shown in the manual.
Note that pins 35 and 36 (Amstrad enumeration) exist on Schneider CPC6128 only due to the use of a 36pin Centronics connector.
| Pin No. (Shugart) | Pin No. (CPC manual) | Signal Name | Description |
| n/a | "35" | N/C | Schneider CPC6128 only |
| 1 (red wire) | 34 | GND | Ground |
| 2 | 33 | N/C (/REDWC) | Density Select 1=Low/0=High |
| 4 | 31 | N/C | Reserved |
| 6 | 29 | N/C | Reserved |
| 8 | 27 | /Index | 0=Index |
| 10 | 25 | N/C (/MOTEA) | -/- (0=Motor Enable Drive 0) |
| 12 | 23 | /DRVSB | Drive Select 1 |
| 14 | 21 | N/C (/DRVSA) | -/-(Drive Select 0) |
| 16 | 19 | /MOTEB | 0=Motor Enable Drive 1 |
| 18 | 17 | /DIR | 0=Direction Select |
| 20 | 15 | /Step | 0=Head Step |
| 22 | 13 | /WDATE | Write Data |
| 24 | 11 | /WGATE | Floppy Write Enable, 0=Write Gate |
| 26 | 9 | /TRK00 | 0=Track 00 |
| 28 | 7 | /WPT | 0=Write Protect |
| 30 | 5 | /RDATA | Read Data |
| 32 | 3 | /SIDE1 | 0=Side 1 Select |
| 34 | 1 (blue wire) | /RDY (/DSKCHG) | 0=Ready (1=Disk Change/0=Ready¹) |
| All others (odd) | All others (even) | GND | Ground |
¹: Although it might look like it, /RDY and /DSKCHG are not compatible. The CPC expects the drive to become ready (=0) by itself, while the DSKCHG signal stays high until confirmation through the PC, so the drive will never become RDY.
