Core1553BRT-EBR Enhanced Bit Rate 1553 Remote Terminal
Word Formats
There are only three types of words in a 1553EBR message: a command word (CW), a data word (DW), and a status
word (SW). Each word consists of a 3-bit sync pattern, 16 bits of data, and a parity bit, providing the 20-bit word (see
Bit
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
CW
Sync
5
RT Address
1
T/R
5
Sub-Address
5
Word Count / Mode Code
1
P
DW
Sync
16
Data
1
P
SW
Sync
5
RT Address
1
Message Error
1
Instrumentation
1
Service Request
3
Reserved
1
Broadcast
Received
1
1
Sub-System Flag
1
Dynamic Bus
Acceptance
1
Terminal Flag
1
Figure 4 •
1553EBR Word Formats
I/O Signal Descriptions
Table 2 •
1553EBR Bus Interface
Port Name
RTADDR[4:0]
RTADDRP
Type
In
In
Description
Sets the RT address; must not be set at '11111'
RT Address parity input. This input should be set high or low to achieve odd parity on the
RTADDR and RTADDRP inputs. If RTADDR is set to '00000', the RTADDRP input should be set
to '1'.
Indicates that the RTADDR and RTADDRP inputs have incorrect parity, or broadcast is enabled
and the RT address is set to 31; when active (high), the RT is disabled and will ignore all
1553EBR traffic.
Active low enable for the A receiver
Data input from the A receiver
Active low enable for the B receiver
Data input from the B receiver
Active high transmitter enable for the A transmitter
Data output to the Bus A transmitter
Active high transmitter enable for the B transmitter
Data output to the Bus B transmitter
RTADERR
Out
BUSAINENn
BUSAIN
BUSBINENn
BUSBIN
BUSAOUTEN
BUSAOUT
BUSBOUTEN
BUSBOUT
Out
In
Out
In
Out
Out
Out
Out
6
A d v a n c e d v 1 .1
Parity
Busy
ACTEL [ Actel Corporation ]
