MA28140

The CPDU I/F generates continuously false output signals in the event that "External Authentication" and "0 octet AU
Trailers" are used (i.e. AUDIS='0', AUEXT='1' and AUTSL='1'). This malfunction is particularly critical for applications using the CPDU I/F for its intended purpose to handle emergency situations.

After generating a first sequence or correct output signals, the state machine driving the CPDU I/F will get caught in a
never-ending loop of states and continue to generate false (pseudo-random) output signals until the PTD is reset by
RESTN='0' or AUDIS='1'. No other command will stop the erroneous outputs of the CPDU I/F. Recommended action by users

The following combination of signal states must not be used : AUDIS='0', AUEXT='1' and AUTSL='1'. This can be ensured by either hardwiring on the PCB or appropriate SW provisions. All users are strongly advised to validate the
functionality of the CPDU I/F operation for their choice of operation modes.

The MA28140 Packet Telecommand Decoder (PTD) is a single-chip implementation of the core part of a telecommand decoder, manufactured using CMOS-SOS high performance, radiation hard, 1.5m technology. The PTD is a full implementation of and fully compliant with the packet telecommand standard ESA PSS-04-107 and the telecommand decoder specification ESA PSS-04-151, these being derived from the corresponding CCSDS standards.

The PTD, which handles 6 NRZ TC input channels, processes the following layers:
Coding Layer
Transfer Layer
Segmentation Layer
Authentication Layer
Command Pulse Distribution

Some of these layers have a telemetry reporting mechanism. The processed TC segment can be transferred to the application either serially or in parallel.