The ATM 155 PMC Card is a mezzanine card designed to be mounted on a CompactPCI carrier or directly on a CompactPCI CPU board with PMC connectors, in order to manage a STM-1/OC-3 optical or electrical interface.
A single 6U board can carry up to 2 ATM 155 PMC cards.
The card includes a Framer and a SAR with PCI interface, provides full handling in hardware of most ATM Adaptation Layers (AAL) and greatly simplifies software management of the remaining ones.
Software selectable electrical (coax) or optical (single- or multi-mode fiber) interfaces provide easy connections both in laboratory and in production environments.

 

Main features STM-1/OC-3 Framer Electrical and optical interface High performance ATM SAR AAL0, AAL3/4, AAL5 support in hardware AAL1, AAL2 support in software

 

SAR (Mindspeed CN8236)
The Service Segmentation and Reassembly Controller (ServiceSAR) delivers a wide range of advanced ATM, AAL, and service-specific features.
These features include, for example, Virtual FIFO buffer segmentation of circuit-based Constant Bit Rate (CBR) traffic and Frame Relay Early Packet Discard (EPD) based on the Discard Eligibility (DE) field.
Other service-level functions enable network level functionalities or topologies.
Two examples of these features include Generic Flow Control (GFC) and echo suppression of multicast data frames on Emulated LAN (ELAN) channels.
The CN8236 provides traffic shaping for all service categories:
• CBR, Variable Bit Rate (VBR)—both single and dual leaky bucket
• Unspecified Bit Rate (UBR)
• Available Bit Rate (ABR)
• GFC—both controlled and uncontrolled flows
• Guaranteed Frame Rate (GFR), that is, guaranteed Minimum Cell Rate (MCR) on UBR Virtual Channel Connections (VCCs)
The internal xBR Traffic Manager automatically schedules each VCC according to user assigned parameters.
The host can implement a congestion notification algorithm for ABR. The controller reduces the Explicit Rate (ER) field or sets the Congestion Indication (CI) bit in Turnaround Resource Management (RM) cells, based on user configuration.

 

Framer (Mindspeed CX28250)
The framer provides a single-access ATM service termination.
The SONET Framer, the ATM Cell Formatter, the UTOPIA Level 2 interface and the clock recovery block provide efficient conversion of SONET frames to ATM cells and vice versa, providing also a software configurable indication for Path Fail or Line Fail alarm condition.
Rx Path: The CX28250 descrambles received data, retrieves the SONET payload envelope. It also processes section, line, and path overhead. ATM cells are extracted from the payload envelope according to the ATM cell delineation standards.
Tx Path: The CX28250 generates a transmit payload pointer and framing bytes. The device also performs HEC generation, idle cell insertion, and ATM cell payload scrambling.
The CX28250 synthesizes the 155.52 MHz transmit clock from a from the internal clock recovery circuit.
It provides facilities for performance monitoring like error detection and correction or insertion of  line and path alarm signals and Remote Defect error insertion.

 

Media Connections
The ATM 155 card provides one STM1/OC3 ATM link with two software selectable interfaces: a SC 1x9 connector (available for multi-mode or single-mode fibre) for optical interface and a coaxial interface with two 75 Ω SMB connectors, in addition to line status indications (LED).
 

Compact PCI Interface
The ATM 155 card provides a compliant 33MHz 32 bit PCI bus interface (PCI v2.1) that can be factory configured to support 5V or 3.3V signalling.
 

EMC & ESD Protection
ESD protection is achieved with correct connection to ground its stand-offs.
The PMC Front Panel is mounted with a gasket that assures electromagnetic protection. The protection level meets the requirements of the IEEE 1101.10 Standard.

Mechanical & Electrical Data 
The ATM 155 card is a single mezzanine card of standard height (10mm), its size is 74mm by 149mm and meets the mechanical and electrical requirements specified by standard IEEE 1386-2000 and 1386.1-2000.
The maximum power consumption is 1A at 3.3V and 500mA at 5V.
The card uses standard EIA-700 AAAB connectors and mounts only Pn1 and Pn2.
 

Software & Drivers 
A wide range of drivers and protocol software is available. Prisma Engineering can also provide custom drivers and software for any operating system or specific requirement.