can result in from 0 to 8 mis- matches (B3 bit errors). This value can be inserted into the Transmit Side G1 byte from bit one to bit four as a Path REI.

The HDMP-3001 contains a 16-bit B3 error counter that counts every B3 bit error. When the perfor- mance monitoring counters are latched (LATCH_EVENT transi- tions high), the value of this counter is latched to the B3ERRCNT[15:0] register, and the B3 error counter is cleared.

3.9.4.9.5Signal Label (C2) Monitoring

The received C2 bytes are moni- tored so that reception of the correct type of payload can be verified. When a consistent C2 value is received for five consecu- tive frames, the accepted value is written to RX_C2[7:0]. The RX_C2_D delta bit is set when a new C2 value is accepted.

The expected value of the re- ceived C2 bytes is provided in EXP_C2[7:0]. If the current ac- cepted value does not match the expected value, and the accepted value is NOT

•the all zeros Unequipped label,

•the 0x01(hex) Equipped - non-specific label,

•0xFC (hex), which in SONET mode indicates non-VT- structured STS-3c SPE with Payload Defect(PDI-P), and in SDH mode is reserved for national use,

•0xFF (hex), which is a reserved label in SONET mode, and in SDH mode indicates VC-AIS,

then the Payload Label Mismatch register bit, RX_PLM, is set high. If the current accepted value is the all zeros Unequipped label, and the provided EXP_C2[7:0]

≠0(hex), then the Unequipped reg-

ister bit, RX_UNEQ, is set high. The RX_PLM and RX_UNEQ sig- nals contribute to the insertion of Path RDI on the Transmit Side G1 byte from bit 5 to bit 7(shown in Table 1). When RX_PLM or RX_UNEQ changes state, the RX_PLM_D or the RX_UNEQ_D delta bit is set.

3.9.4.9.6 Path REI Monitoring

Bits 1 through 4 (the four MSBs) of the path status byte indicate the number of B3 errors that were detected by the remote terminal in its received SPE/VC signal. Only the binary values between 0 and 8 are legitimate. If a value greater than 8 is received, it is in- terpreted as zero errors (as is specified in GR-253 and ITU-T Recommendation G.707). The HDMP-3001 contains a 16-bit G1 error counter that counts every error indicated by G1 When the performance monitoring counters are latched (LATCH_EVENT tran- sitions high), the value of this counter is latched to the

G1_ERRCNT[15:0] register, and the G1 error counter is cleared.

3.9.4.9.7Path RDI Monitoring

The HDMP-3001 can be set to monitor bit 5 of G1 (RDI-P indica- tor), if RX_PRDI5 = 1; or bits 5, 6 and 7 of G1 (enhanced RDI-P indi- cator), if RX_PRDI5 = 0. Monitoring consists of checking for G1_CONSEC[3:0] consecutive received values of the monitored bit(s) that are identical. When a consistent value is received, bits 5, 6 and 7 of G1 are written to RX_G1[2:0]. Accepted values are compared to the previous con- tents of this register. (All three bits are written, but if RX_PRDI5 = 1, only G1 bit 5 and RX_G1[2] are involved in the comparisons.) When a new value is stored, the RX_G1_D delta bit is set.

In SONET mode, an STS SPE de- tects an RDI-P defect when an RDI-P signal is received for five to ten consecutive frames and termi- nates the RDI-P defect when a zero is in bits 5 and 6 of the G1 byte for five to ten consecutive frames. It does not detect an RDI-

Pdefect and terminate the RDI-P defect when it has detected an AIS-P defect on the affected path.

3.9.4.9.8 Other POH Bytes

The remaining POH bytes are not monitored by the HDMP-3001. These include the path user chan- nel (F2), the position indicator (H4), the path growth/user chan- nel (Z3/F3), the path growth/path APS channel (Z4/K3), and the tan- dem connection monitoring (Z5/ N1) bytes.

3.9.4.10STS-3C/STM-1 Framer

The HDMP-3001 receive framer operates in two modes. If RX_FRMR_INH = 0 (the default), the HDMP-3001 device framer is enabled. In this mode, the parallel input signal is not assumed to be byte aligned. The SONET/SDH framer locates the framing bytes in the selected data signal to find byte alignment and determine the position of all TOH/SOH bytes. After finding frame, the framer shifts the data so that its output data is byte aligned. It also de- scrambles the data, performs B1 monitoring, and provides frame counter outputs.

If RX_FRMR_INH = 1, the framer circuitry in the HDMP-3001 is by- passed. In this mode, the HDMP-3001 requires a frame start indication, RX_FRAME_IN, as well as data and clock. The data may come from a high-speed de- vice that performs framing and serial-to-parallel conversion of an STS-3c/STM-1 signal or from a

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Agilent Technologies HDMP-3001 manual Path REI Monitoring, Path RDI Monitoring, STS-3C/STM-1 Framer
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HDMP-3001 specifications

Agilent Technologies, a prominent name in electronics and measurement technology, offers a wide range of products that cater to various industries. Among its notable offerings is the HDMP-3001, a high-speed, serial data transceiver designed to facilitate robust communications in electronic systems. The HDMP-3001 stands out with its ability to handle high bandwidths, making it particularly suited for applications requiring rapid data transfer, such as telecommunications, computer networking, and high-performance computing.

One of the main features of the HDMP-3001 is its advanced signaling technology. By employing differential signaling, the transceiver minimizes electromagnetic interference and enhances signal integrity. This is crucial in environments with multiple electronic devices operating simultaneously, as it ensures data is transmitted clearly and without degradation.

The HDMP-3001 operates at a maximum data rate of 1 Gbps, allowing for efficient data transfer over short distances. This capability is coupled with a flexible architecture that enables users to configure the transceiver for various applications. The device supports both point-to-point and point-to-multipoint configurations, giving engineers the versatility they need in designing communication links.

Moreover, the HDMP-3001 features on-chip clock recovery functionality, which simplifies system design by reducing the number of external components needed. This built-in feature allows the transceiver to maintain synchronization even as data rates increase, further enhancing performance.

The low power consumption characteristic of the HDMP-3001 is another notable advantage. This makes it an attractive choice for battery-operated devices and systems where power efficiency is critical. The transceiver’s design ensures optimal performance while minimizing heat generation and power draw, enabling longer operational lifetimes.

In terms of physical characteristics, the HDMP-3001 comes in a compact, surface-mount package, allowing for easier integration into various circuit board designs. The small form factor, combined with its innovative technology, makes it a popular choice among engineers seeking to improve data transmission reliability without compromising on space or power constraints.

Overall, Agilent Technologies' HDMP-3001 is a formidable solution for high-speed serial data transmission, characterized by its robust performance, low power consumption, and versatile configuration options. With these features, it continues to be an essential component in the evolving landscape of electronic communications.
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