Allied Vision Technologies Pike Manual de Instruções descarregar pdf (Página 24)

FireWire

PIKE Technical Manual V4.0.0

Capabilities of 1394a (FireWire 400)

FireWire 400 (S400) is able to transfer data between devices at 100, 200 or

400 MBit/s data rates. Although USB 2.0 claims to be capable of higher

speeds (480 Mbit/s), FireWire is, in practice, not slower than USB 2.0.

The 1394a capabilities in detail:

• 400 Mbit/s

• Hot-pluggable devices

• Peer-to-peer communications

• Direct Memory Access (DMA) to host memory

• Guaranteed bandwidth

• Multiple devices (up to 45 W) powered via FireWire bus

IIDC V1.3 camera control standards

IIDC V1.3 released a set of camera control standards via 1394a which estab-

lished a common communications protocol on which most current FireWire

cameras are based.

In addition to common standards shared across manufacturers, a special

Format_7 mode also provided a means by which a manufacturer could offer

special features (smart features), such as:

•higher resolutions

• higher frame rates

•diverse color modes

as extensions (advanced registers) to the prescribed common set.

Capabilities of 1394b (FireWire 800)

FireWire 800 (S800) was introduced commercially by Apple in 2003 and has

a 9-pin FireWire 800 connector (see details in Chapter IEEE 1394b port pin

assignment on page 86). This newer 1394b specification allows a transfer

rate of 800 MBit/s with backward compatibilities to the slower rates and 6-

pin connectors of FireWire 400.

The 1394b capabilities in detail:

• 800 Mbit/s

• All previous benefits of 1394a (see above)

• Interoperability with 1394a devices

• Longer communications distances (up to 500 m using GOF cables)

IIDC V1.31 camera control standards

Twinned with 1394b, the IIDC V1.31 standard arrived in January 2004, evolv-

ing the industry standards for digital imaging communications to include I/

O and RS232 handling, and adding further formats. At such high bandwidths

it has become possible to transmit high-resolution images to the PC’s mem-

ory at very high frame rates.

1 2 ... 19 20 21 22 23 24 25 26 27 28 29 ... 331 332

Sem comentários

Allied Vision Technologies Pike Manual de Instruções Página 24