ATA CD-ROM 50 pin Internal (notebook)

See ATA (Advanced Technology Attachment) Internal for more information and 40pin pinout.

50 pin IDC male connector at the controller and peripherals.

50 pin IDC female connector at the cable.

The ATA CD-ROM 50-pin internal notebook connector is a JAE-style 50-pin interface defined by SFF-8020 Rev 1.2 (Small Form Factor Committee, February 1994) and subsequently incorporated into the ANSI/INCITS ATA/ATAPI-4 standard (INCITS 317-1998). It extends the standard 40-pin ATA/IDE bus for use in notebook optical drives by prepending three analogue audio pins (pins 1–3) and appending five +5 V power lines and four ground lines, so that the ATA signals appear offset by four positions relative to the desktop connector. The ATAPI packet interface layer, also defined by SFF-8020, allows CD-ROM and other removable-media devices to share an IDE bus with hard disks by using SCSI-derived packet commands over the ATA register set.

Notes

• Direction is controller relative to device (CD-ROM drive).
• The connector is a JAE-style 50-pin unit at 2.0 mm pitch, physically keyed to prevent incorrect insertion.
• Pin 4 is ground and acts as a separator between the analogue audio block (pins 1–3) and the ATA signal block (pins 5–37).
• The five +5 V lines (pins 38–42) supply both logic and spindle-motor power; the four ground return lines (pins 43–46) complete the power circuit, eliminating the need for a separate power connector.
• Pins 47 (Device Cfg) and 49–50 (reserved) are vendor-specific; pin 47 may be used for Spindle Sync or Cable Select depending on the drive manufacturer.
• The ATA/IDE signals on pins 5–37 are TTL-compatible; cable maximum length is approximately 18 inches (450 mm).

Signals

• Audio Left — analogue audio left-channel output from the CD-ROM drive; used for direct audio output to the notebook’s sound subsystem.
• Audio Right — analogue audio right-channel output from the CD-ROM drive.
• Audio ground — ground reference for the analogue audio signals; kept separate from digital ground to reduce noise.
• GND — digital ground.
• /RESET — host-asserted reset; initialises the drive when driven low.
• DD0–DD15 — 16-bit bidirectional data bus; data is transferred in 16-bit words between host and drive.
• DMARQ — DMA request; asserted by the drive to request a DMA transfer cycle (direction varies by transfer mode).
• /DIOR — I/O read strobe from the host; clocks data from the drive onto the bus.
• /DIOW — I/O write strobe from the host; clocks data from the host into the drive.
• IORDY — I/O ready; drive de-asserts this line to insert wait states when it cannot complete a transfer in the current cycle.
• /DMACK — DMA acknowledge from the host; qualifies a DMA data transfer cycle.
• INTRQ — interrupt request; asserted by the drive to signal command completion or an attention condition to the host.
• /IOCS16 — 16-bit I/O chip-select; asserted by the drive to indicate 16-bit data port capability.
• DA0–DA2 — three-bit register address bus from the host; selects the ATA task-file register.
• PDIAG — passed diagnostics; asserted by the drive-1 device to indicate successful self-test (also used for DASP handshake during initialisation).
• /IDE_CS0 — chip-select 0; enables the primary ATA task-file registers (I/O addresses 1F0h–1F7h).
• /IDE_CS1 — chip-select 1; enables the alternate status and device-control registers (I/O addresses 3F6h–3F7h).
• /ACTIVE (/DASI/DASP) — drive active / slave present; open-drain signal used both to illuminate the drive activity LED and to indicate the presence of a slave device during power-on negotiation.
• +5V (pins 38–42) — five +5 V supply lines providing logic and spindle-motor power.
• GND (pins 43–46) — power-return ground lines.
• Device Cfg (pin 47) — device configuration; use varies by manufacturer; may implement Spindle Sync or Cable Select.
• reserved (pins 49–50) — reserved for vendor-unique use; not defined by SFF-8020.

References

• ATA Packet Interface for CD-ROMs — SFF-8020 Rev 1.2
• T13 AT Attachment — Standards (Expired/Withdrawn)

Category:Data Storage Connectors