MA28138
MARCH 1995
PRELIMINARY INFORMATION
DS3591-4.4
MA28138
OBDH REMOTE BUS INTERFACE
The MA28138 is an OBDH Remote Bus Interface (RBI)
that provides the facilities required by a modern packet OBDH
bus system but at the same time preserves compatibility with
existing RTU hardware and software. Designed under an ESA
contract, the RBI ASIC implements the ESA RBI-2 Remote
Bus Interface and 8-bit Broadcast Polling protocols for
transfers of data between the OBDH DBI bus and processor
memory.
Linked to the OBDH bus via a bus terminal (MA28139
OBT), the RBI executes central terminal instructions from the
Interrogation bus including mission configurable user
commands and status. The RBI handshakes all CTU
commands on the Response bus and traps DMA errors. The
RBI supports bi-directional data transfers on the Response
bus allowing the possibility of working without a Block Transfer
bus. The inclusion of a Block Transfer bus using this RBI in an
OBDH system will increase its throughput capacity by about a
factor of four.
RIRSYNC
RIRCLK
RIRDATA
RIRVAL
SREQ
BIL(0:5)
UCC(0:6)
UCCS
USER
I-BUS
RRRCLK
RRRVAL
RRRDATA
RRRINIT
RRTDATA
RRTEN
R-BUS
DBI
OSC
SYNCN
AD(0:15)
AS
DSN
RBRCLK
RBRDATA
RBRVAL
RBRINIT
RBTDATA
RBTEN
µP BUS
RDPWN
MPION
INPOPN
DMADDN
RDYN
RBI
BT-BUS
SYNDN
TA(0:5)
EXTFMT
EXTAEN
ADDRESSING
DMARN
DMAKN
DONE
DMA
GI(0:1)
BROADCAST
POLL
TFRERR
PBP(0:4)
FEATURES
■ Radiation Hard
BCP(1:4)
BCPVAL
MRSTN
RESET
BROADCAST
PULSES
■ Low Power Consumption
■ Single CMOS-SOS ASIC Implementation
■ Direct Connection to Processor Address/Data and Control
Figure 1: Block Diagram
Busses
■ Programmable User-to-User Group Transfers
■ Can Support Bi-directional DMA Transfers without Block
Transfer Bus
■ Block Transfers Supported
■ Fully Compliant with ESA RBI-2 Protocol, ESTEC
WDI/CS/928
1
ZARLINK [ ZARLINK SEMICONDUCTOR INC ]
