Instruction manual
Guppy PRO Technical ManualV4.1.0
229
Configuration of the camera
Maximum ISO packet size
Use this feature to increase the MaxBytePerPacket value of Format_7 modes.
This overwrites the maximum allowed isochronous packet size specified by IIDC
V1.31.
Example For isochronous packets at a speed of S800 the maximum allowed packet size
(IIDC V1.31) is 8192 byte. This feature allows you to extend the size of an iso-
chronous packet up to 11.000 byte at S800. Thus, the isochronous bandwidth is
increased from 64 MByte/s to approximately 84 MByte/s. You need either PCI
Express or PCI-X (64 bit).
The Maximum ISO packet size feature ...
• ... reduces the asynchronous bandwidth available for controlling cameras
by approximately 75%
• ... may lead to slower responses on commands
• ... is not covered by the IEEE 1394 specification
• ... may not work with all available 1394 host adapters.
Register Name Field Bit Description
0xF1000560 ISOSIZE_S400 Presence_Inq [0] Indicates presence of this feature (read only)
--- [1..5] Reserved
ON_OFF [6] Enable/Disable S400 settings
Set2Max [7] Set to maximum supported packet size
--- [8..15] Reserved
MaxIsoSize [16..31] Maximum ISO packet size for S400
0xF1000564 ISOSIZE_S800 Presence_Inq [0] Indicates presence of this feature (read only)
--- [1..5] Reserved
ON_OFF [6] Enable/Disable S800 settings
Set2Max [7] Set to maximum supported packet size
--- [8..15] Reserved
MaxIsoSize [16..31] Maximum ISO packet size for S800
Table 145: Advanced register: Maximum ISO packet size
Note
We strongly recommend to use PCI-X (64 bit) or PCI Express
adapter.