UT1553B BCRTB (5/16) - EOL

MIL-STD-1553
UT1553BCRT Version B
Released Datasheet
Cobham.com/HiRel
May 27, 2016
The most important thing we build is trust
FEATURES
 Comprehensive MIL-STD-1553B dual-redundant Bus
Controller (BC) and Remote Terminal (RT) functions
 MIL-STD-1773 compatible
 Multiple message processing capability in BC and RT
modes
 Time-tagging and message logging in RT mode
 Automatic polling and intermessage delay in BC mode
 Programmable interrupt scheme and internally
generated interrupt history list
1553
DATA
CHANNEL
B
TIMERON
DUAL
CHANNEL
ENCODER/
DECODER
MODULE
TIMEOUT
CONTROL
STATUS
CURRENT BC/RT
DESCRIPTOR SPACE
INTERRUPT
HANDLER
CLOCK &
RESET
LOGIC
1553
DATA
CHANNEL
A
REGISTERS
HIGH-PRIORITY
STD PRIORITY LEVEL
STD PRIORITY PULSE
MASTER
RESET
12MHZ
 Register-oriented architecture to enhance
programmability
 DMA memory interface with 64K addressability
 Internal self-test
 Remote terminal operations in ASD/ENASD-certified
(SEAFAC)
 Packaged in 84-pin pingrid array and 84-lead flatpack
 Standard Microcircuit Drawing 5962-88628
 available - QML Q
POLLING COMPARE
SERIAL to
PARALLELCONVERSION
BC PROTOCOL
& MESSAGE
HANDLER
16
PARALLELTO-SERIAL
CONVERSION
ADDRESS
GENERATOR
BUILT-IN-TEST WORD
BUS
TRANSFER
LOGIC
CURRENT COMMAND
INTERRUPT LOG
LIST POINTER
16
HIGH-PRIORITY
INTERRUPT ENABLE
16
RT PROTOCOL
& MESSAGE
HANDLER
16
16
DMA/CPU
CONTROL
HIGH-PRIORITY
INTERRUPT STATUS/RESET
16
BUILTINTEST
STANDARD INTERRUPT
ENABLE
RT ADDRESS
BUILT-IN-TEST
START COMMAND
PROGRAMMED RESET
DMA ARBITRATION
REGISTER CONTROL
RT TIMER TAG
RESET COMMAND
ADDRESS
DUAL-PORT MEMORY CONTROL
16
16
DATA
Figure 1. BCRT Block Diagram
36-00-09-000
Revision 1.0.0
1
Cobham Semiconductor Solutions
Cobham.com/HiRel
Table of Contents
1.0 INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1 Features - Remote Terminal (RT) Mode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.2 Features - Bus Controller (BC) Mode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.0 PIN IDENTIFICATION AND DESCRIPTION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
3.0 INTERNAL REGISTERS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
4.0 SYSTEM OVERVIEW. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
5.0 SYSTEM INTERFACE . . . . . . . . .
5.1 DMA Transfers. . . . . . . . . . . .
5.2 Hardware Interface. . . . . . . . .
5.3 CPU Interconnection. . . . . . . .
5.4 RAM Interface
.............
5.5 Transmitter/Receiver Interface.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
18
18
18
18
20
20
6.0 REMOTE TERMINAL ARCHITECTURE . . . . .
6.1 RT Functional Operation. . . . . . . . . . . . . .
6.1.1 RT Subaddress Descriptor Definitions.
6.1.2 Message Status Word. . . . . . . . . . . .
6.1.3 Mode Code Descriptor Definition. . . .
6.2 RT Error Detection. . . . . . . . . . . . . . . . . .
6.3 RT Operational Sequence
..............
..
..
..
..
..
..
..
..
..
..
..
..
..
..
.
.
.
.
.
.
.
..
..
..
..
..
..
..
.
.
.
.
.
.
.
..
..
..
..
..
..
..
..
..
..
..
..
..
..
.
.
.
.
.
.
.
..
..
..
..
..
..
..
.
.
.
.
.
.
.
.
.
.
.
.
.
.
..
..
..
..
..
..
..
.
.
.
.
.
.
.
..
..
..
..
..
..
..
..
..
..
..
..
..
..
.
.
.
.
.
.
.
..
..
..
..
..
..
..
..
..
..
..
..
..
..
.
.
.
.
.
.
.
..
..
..
..
..
..
..
.
.
.
.
.
.
.
.
.
.
.
.
.
.
21
21
21
23
24
26
26
7.0 BUS CONTROLLER ARCHITECTURE
7.1 BC Functional Operation. . . . . . . .
7.2 Polling . . . . . . . . . . . . . . . . . . . .
7.3 BC Error Detection. . . . . . . . . . . .
7.4 BC Operational Sequence
........
7.5 BC Operational Example. . . . . . . .
..
..
..
..
..
..
..
..
..
..
..
..
.
.
.
.
.
.
..
..
..
..
..
..
.
.
.
.
.
.
..
..
..
..
..
..
..
..
..
..
..
..
.
.
.
.
.
.
..
..
..
..
..
..
.
.
.
.
.
.
.
.
.
.
.
.
..
..
..
..
..
..
.
.
.
.
.
.
..
..
..
..
..
..
..
..
..
..
..
..
.
.
.
.
.
.
..
..
..
..
..
..
..
..
..
..
..
..
.
.
.
.
.
.
..
..
..
..
..
..
.
.
.
.
.
.
.
.
.
.
.
.
27
28
30
30
30
32
.
.
.
.
.
.
..
..
..
..
..
..
..
..
..
..
..
..
.
.
.
.
.
.
8.0 EXCEPTION HANDLING AND INTERRUPT LOGGING . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
9.0 MAXIMUM AND RECOMMENDED OPERATING CONDITIONS . . . . . . . . . . . . . . . . . . . . . 36
10.0 DC ELECTRICAL CHARACTERISTICS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
11.0 AC ELECTRICAL CHARACTERISTICS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
12.0 PACKAGE OUTLINE DRAWINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
13.0 ORDERING INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
36-00-09-000
Revision 1.0.0
2
Cobham Semiconductor Solutions
Cobham.com/HiRel
1.0 INTRODUCTION
Programmable Interrupt Selection
The monolithic CMOS UT1553B BCRT provides the system
designer with an intelligent solution to MIL-STD-1553B
multiplexed serial data bus design problems. The UT1553B
BCRT is a single-chip device that implements two of the
defined MIL-STD-1553B functions - Bus Controller and
Remote Terminal. Designed to reduce host CPU overhead,
the BCRT’s powerful state machines automatically execute
message transfers, provide interrupts, and generate status
information. Multiple registers offer many programmable
functions as well as extensive information for host use. In
the BC mode, the BCRT uses a linked-list message scheme
to provide the host with message chaining capability. The
BCRT enhances memory use by supporting variable-size,
relocatable data blocks. In the RT mode, the BCRT
implements time-tagging and message history functions. It
also supports multiple (up to 128) message buffering and
variable length messages to any subaddress.
The host CPU can select various events to cause an interrupt
with provision for high and standard priority interrupts.
Interrupt History List
The BCRT provides an Interrupt History List that records,
in the order of occurrence, the events that caused the
interrupts. The list length is programmable.
1.2 Features - Bus Controller (BC) Mode
Multiple Message Processing
The BCRT autonomously processes any number of
messages or lists of messages that may be stored in a 64K
memory space.
Automatic Intermessage Delay
When programmed by the host, the BCRT can delay a hostspecified time before executing the next message in
sequence.
The UT1553B BCRT is an intelligent, versatile, and easy to
implement device -- a powerful asset to system designers.
Automatic Polling
When polling, the BCRT interrogates the remote terminals
and then compares their status word responses to the
contents of the Polling Compare Register. The BCRT can
interrupt the host CPU if an erroneous remote terminal
status word response occurs.
1.1 Features - Remote Terminal (RT) Mode
Indexing
The BCRT is programmable to index or buffer messages on
a subaddress-by-subaddress basis. The BCRT, which can
index as many as 128 messages, can also assert an interrupt
when either the selected number of messages is reached
or every time a specified subaddress is accessed.
Automatic Retry
The BCRT can automatically retry a message on busy,
message error, and/or response time-out conditions. The
BCRT can retry up to four times on the same or on the
alternate bus.
Variable Space Allocation
The BCRT can use as little or as much memory (up to 64K)
as needed.
Programmable Interrupt Selection
The host CPU can select various events to cause an interrupt
with provision for high and standard priority interrupts.
Selectable Data Storage
Address programmability within the BCRT provides flexible
data placement and convenient access.
Interrupt History List
Sequential Data Storage
The BCRT stores/retrieves, by subaddress, all messages in
the order in which they are transacted.
The BCRT provides an Interrupt History List that records,
in the order of occurrence, the events that caused the
interrupts. The list length is program- mable.
Sequential Message Status Information
Variable Space Allocation
The BCRT provides message validity, time-tag, and wordcount information, and stores it sequentially in a separate,
cross-referenced list.
The BCRT uses as little or as much memory (up to 64K) as
needed.
Illegalizing Mode Codes and Subaddresses
Address programmability within the BCRT provides flexible
data placement and convenient access.
Selectable Data Storage
The host can declare mode codes and subaddresses illegal
by setting the appropriate bit(s) in memory.
36-00-09-000
Revision 1.0.0
3
Cobham Semiconductor Solutions
Cobham.com/HiRel
2.0 PIN IDENTIFICATION AND DESCRIPTION
BIPHASE OUT
TAZ
TAO
TBZ
TBO
13
14
17
18
(K3)
(L2)
(L4)
(K6)
BIPHASE IN
RAZ
RAO
RBZ
RBO
15
16
19
20
(L3)
(K4)
(K5)
(L5)
TERMINAL
ADDRESS* *
RTA0
RTA1
RTA2
RTA3
RTA4
RTPTY
28
29
30
31
32
33
(K8)
(L9)
(L10)
(K9)
(L11)
(K10)
STATUS
SIGNALS
STDINTL
STDINTP
HPINT
TIMERON
COMSTR
SSYSF
BCRTF
CHA/B
TEST
68
69
70
25
27
72
75
26
73
(A6) +
(A4)
(B4) +
(K7)
(L8)
(A2)
(B2)
(J7)
(B3)*
DMAR
DMAG
DMAGO
DMACK
BURST
TSCTL
56
57
67
58
74
55
(A10) +
(A9)
(B5)
(B8) +
(A1)
(B9)
DMA
SIGNALS
RD
WR
CS
AEN
BCRTSEL
LOCK
CONTROL
MRST
SIGNALS
EXTOVR
RRD
RWR
MEMCSI
MEMCSO
**
+
++
*
61
60
62
66
11
12
10
24
53
52
59
54
(B7)
(C7)
(A7)
(A5)
(L1) * *
(K2) * *
(J2)
(L7) * *
(A11)
(C10)
(A8) * *
(B10)
Pin internally pulled up.
Pin at high impedance when not asseted
Bidirectional pin.
Formerly MEMWIN.
(J10)
(K11)
(J11)
(H10)
(H11)
(G9)
(G10)
(G11)
(E9)
(E11)
(E10)
(F11)
(D11)
(D10)
(C11)
(B11)
34
35
36
37
38
39
40
41
44
45
46
47
48
49
50
51
A0 ++
A1 ++
A2 ++
A3 ++
A4
A5
A6
A7
A8
A9
A10
A11
A12
A13
A14
A15
ADDRESS+
LINES
(K1)
(J1)
(H2)
(H1)
(G3)
(G2)
(G1)
(F1)
(E1)
(E2)
(F2)
(D1)
(D2)
(C1)
(B1)
(C2)
9
8
7
6
5
4
3
2
83
82
81
80
79
78
77
76
D0
D1
D2
D3
D4
D5
D6
D7
D8
D9
D10
D11
D12
D13
D14
D15
DATA
++
LINES
(L6)
(F9)
(C6)
(E3)
23
43
64
84
VDD
VDD
VDD
VDD
POWER
(F3)
(J6)
(F10)
(B6)
1
22
42
63
VSS
VSS
VSS
VSS
GROUND
(J5)
(C5)
(A3)
21
65
71
CLK
MCLK
MCLKD2
CLOCK
SIGNALS
( ) Pingrid arraylead identification in parentheses.
LCC, flatpack pin number not in parentheses.
Figure 2a. BCRT 84-lead Functional Pin Description
36-00-09-000
Revision 1.0.0
4
Cobham Semiconductor Solutions
Cobham.com/HiRel
Legend for TYPE and ACTIVE fields:
TUI = TTL input (pull-up)
AL = Active low
AH = Active high
ZL = Active low - inactive state is high impedance
TI = TTL input
TO = TTL output
TTO = Three-state TTL output
TTB = Bidirectional
Notes:
1. Address and data buses are in the high-impedance state when idle.
ADDRESS BUS
NAME
36-00-09-000
Revision 1.0.0
PIN NUMBER
TYPE ACTIVE
DESCRIPTION
FP
PGA
A0
34
J10
TTB
--
Bit 0 (LSB) of the Address Bus
A1
35
K11
TTB
--
Bit 1 of the Address Bus
A2
36
J11
TTB
--
Bit 2 of the Address Bus
A3
37
H10
TTB
--
Bit 3 of the Address Bus
A4
38
H11
TTO
--
Bit 4 of the Address Bus
A5
39
G9
TTO
--
Bit 5 of the Address Bus
A6
40
G10
TTO
--
Bit 6 of the Address Bus
A7
41
G11
TTO
--
Bit 7 of the Address Bus
A8
44
E9
TTO
--
Bit 8 of the Address Bus
A9
45
E11
TTO
--
Bit 9 of the Address Bus
A10
46
E10
TTO
--
Bit 10 of the Address Bus
A11
47
F11
TTO
--
Bit 11 of the Address Bus
A12
48
D11
TTO
--
Bit 12 of the Address Bus
A13
49
D10
TTO
--
Bit 13 of the Address Bus
A14
50
C11
TTO
--
Bit 14 of the Address Bus
A15
51
B11
TTO
--
Bit 15 (MSB) of the Address Bus
5
Cobham Semiconductor Solutions
Cobham.com/HiRel
DATA BUS
NAME
PIN NUMBER
TYPE
ACTIVE
DESCRIPTION
FP
PGA
D0
9
K1
TTB
--
Bit 0 (LSB) of the Data Bus
D1
8
J1
TTB
--
Bit 1 of the Data Bus
D2
7
H2
TTB
--
Bit 2 of the Data Bus
D3
6
H1
TTB
--
Bit 3 of the Data Bus
D4
5
G3
TTB
--
Bit 4 of the Data Bus
D5
4
G2
TTB
--
Bit 5 of the Data Bus
D6
3
G1
TTB
--
Bit 6 of the Data Bus
D7
2
F1
TTB
--
Bit 7 of the Data Bus
D8
83
E1
TTB
--
Bit 8 of the Data Bus
D9
82
E2
TTB
--
Bit 9 of the Data Bus
D10
81
F2
TTB
--
Bit 10 of the Data Bus
D11
80
D1
TTB
--
Bit 11 of the Data Bus
D12
79
D2
TTB
--
Bit 12 of the Data Bus
D13
78
C1
TTB
--
Bit 13 of the Data Bus
D14
77
B1
TTB
--
Bit 14 of the Data Bus
D15
76
C2
TTB
--
Bit 15 (msb) of the Data Bus
TERMINAL ADDRESS INPUTS
NAME
36-00-09-000
Revision 1.0.0
PIN NUMBER
TYPE
ACTIVE
DESCRIPTION
FP
PGA
RTA0
28
K8
TUI
--
Remote Terminal Address Bit 0 (LSB). The entire
RT address is strobed in at Master Reset. Verify it
by reading the Remote Terminal Address Register.
All the Remote Terminal Address bits are internally
pulled up.
RTA1
29
L9
TUI
--
Remote Terminal Address Bit 1. This is bit 1 of the
Remote Terminal Address.
RTA2
30
L10
TUI
--
Remote Terminal Address Bit 2. This is bit 2 of the
Remote Terminal Address.
RTA3
31
K9
TUI
--
Remote Terminal Address Bit 3. This is bit 3 of the
Remote Terminal Address.
RTA4
32
L11
TUI
--
Remote Terminal Address Bit 4. This is bit 4 (MSB)
of the Remote Terminal Address.
RTPTY
33
K10
TUI
--
Remote Terminal (Address) Parity. This is odd of
the Remote Terminal Address.
6
Cobham Semiconductor Solutions
Cobham.com/HiRel
CONTROL SIGNALS
NAME
PIN NUMBER
TYPE
ACTIVE
DESCRIPTION
FP
PGA
RD
61
B7
TI
AL
Read. The host uses this in conjunction with CS to read an internal
BCRTM register.
WR
60
C7
TI
AL
Write. The host uses this in conjunction with CS to write an internal
BCRTM register.
CS
62
A7
TI
AL
Chip Select. This selects theBCRT when accessing the BCRTM ’s internal
register.
AEN
66
A5
TI
AH
Address Enable. The host CPU uses AEN to indicate to the BCRTM that
the BCRTM ’s addresslines can be asserted; this is a precautionary signal
provided to avoid address bus crash. If not used, it must be tied high.
BCRTSEL
11
L1
TUI
--
BC/RT Select. This selects between either the Bus Controller or Remote
Terminal mode. The BC/RT Mode Select bit in the Control Register
overrides this input if the Lock pin is not high. This pin is internally pulled
high.
LOCK
12
K2
TUI
AH
Lock. When set, this pin prevents internal changes to both the RT
address and BC/RT mode select functions. This pin is internally pulled
high.
EXTOVR
24
L7
TUI
AL
External Override. Use this in multi-redundant applications. Upon
receipt, the BCRTM aborts all current activity. EXTOVR should be
connected to COMSTR output of the adjacent BCRTM when used. This
pin is internally pulled high.
MRST
10
52
TI
AL
Master Reset. This resets all internal state machines, encoders,
decoders, and registers. The minimum pulse width for a successful
Master Reset is 500ns.
MEMCSO
54
B10
TO
AL
Memory Chip Select Out. This is the regenerated MEMCSI inout for
external RAM during the pseudo-dual-port RAM mode. The BCRTM also
uses it to select external memory during memory accesses.
MEMCSI
59
A8
TUI
AL
Memory Chip Select In. Used in the pseudo-dual-port RAM mode only,
MEMCSI is received from the host and is propagated through to
MEMCSO.
RRD
53
A11
TO
AL
RAM Read. In the pseudo-dual-port RAM mode, the host uses this signal
in conjunction with MEMCSO to read from external RAM through the
BCRTM . It is also the signal the BCRTM uses to read from memory. It
is asserted following receipt of DMAG. When the BCRTM performs
multiple reads, this signal is pulsed.
RWR
52
C10
TO
AL
RAM Write. In the pseudo-dual-port RAM mode, the CPU and BCRTM
use this to write to external RAM. This signal is asserted following receipt
of DMAG. For multiple writes, this signal is pulsed.
36-00-09-000
Revision 1.0.0
7
Cobham Semiconductor Solutions
Cobham.com/HiRel
CONTROL SIGNALS Cont’d
NAME
PIN NUMBER
TYPE
ACTIVE
DESCRIPTION
FP
PGA
STDINTL
68
A6
TTO
ZL
Standard Interrupt Level. This is a level interrupt. It is asserted
when one or more events enabled in either the Standard Interrupt
Enable Register, RT Descriptor, or BC Command Block occur.
Resetting the Standard Interrupt bit in the High-Priority Interrupt
Status/Reset Register clears the interrupt.
STDINTP
69
A4
TO
AL
Standard Interrupt Pulse. STDINTP pulses when an interrupt is
logged.
HPINT
70
B4
TTO
ZL
High-Priority Interrupt. The High Priority Interrupt level is asserted
upon occurance of events enabled in the High-Priority Interrupt
Enable Register. The corresponding bit(s) in the High-Priority
Interrupt Status/Reset Register reset HPINT.
TIMERON
25
K7
TO
AL
(RT) Timer On. This is a 760-microsecond fail-safe transmitter
enable timer. Started at the beginning of a transmission, TIMERON
goes inactive 760 microseconds later or is reset automatically with
the receipt of a new command. Use it in conjunction with CHA/B
output to provide a fail-safe timer for Channels A and B
transmitters.
COMSTR
27
L8
TO
AL
(RT) Command Strobe. The BCRTM asserts this signal after
receiving a valid command. The BCRTM deactivates it after
servicing the command.
SSYSF
72
A2
TI
AH
(RT) Command Strobe. The BCRTM asserts this signal after
receiving a valid command. The BCRTM deactivates it after
servicing the command.
BCRTF
75
B2
TO
AH
BCRTM Fail. This indicates a Built-in-Test (BIT) failure. In the RT
mode, the Terminal Flag bit in 1553 status word is also set.
CHA/B
26
59
TO
--
Channel A/B. This indicates the active or last active channel.
TEST
73
B3
TO
AL
BCRTM Fail. This indicates a Built-in-Test (BIT) failure. In the RT
mode, the Terminal Flag bit in 1553 status word is also set.
36-00-09-000
Revision 1.0.0
8
Cobham Semiconductor Solutions
Cobham.com/HiRel
BIPHASE INPUTS
NAME
PIN NUMBER
TYPE
ACTIVE
DESCRIPTION
FP
PGA
RAO
16
K4
TI
--
Receive Channel A One. This is the Manchester-encoded true signal input
from Channel A of the bus receiver.
RAZ
15
L3
TI
--
Receive Channel A Zero. This is the Manchester-encoded complementary
signal input from Channel A of the bus receiver.
RBO
20
L5
TI
--
Receive Channel B One. This is the
Manchester-encoded true signal
input from Channel B of the bus receiver.
RBZ
19
K5
TI
--
Receive Channel B Zero. This is the Manchester-encoded complementary
signal input from Channel B of the bus receiver.
BIPHASE OUTPUTS
NAME
36-00-09-000
Revision 1.0.0
PIN NUMBER
TYPE
ACTIVE
DESCRIPTION
FP
PGA
TAO
14
L2
TO
--
Transmit Channel A One. This is the Manchester-encoded true
output to be connected to the Channel A bus transmitter input.
This signal is idle low.
TAZ
13
K3
TO
--
Transmit Channel A Zero. This is the Manchester-encoded
complementary output to be connected to the Channel A bus
transmitter input. This signal is idle low.
TBO
18
K6
TO
--
Transmit Channel B One. This is the Manchester-encoded true
output to be connected to the Channel B bus transmitter input.
This signal is idle low.
TBZ
17
L4
TO
--
Transmit Channel B Zero. This is the Manchester-encoded
complementary output to be connected to the Channel B bus
transmitter input. This signal is idle low.
9
Cobham Semiconductor Solutions
Cobham.com/HiRel
DMA SIGNALS
NAME
PIN NUMBER
TYPE
ACTIVE
DESCRIPTION
FP
PGA
DMAR
56
A10
TTO
ZL
DMA Request. The BCRTM issues this signal when access to RAM is
required. It goes inactive after receiving a DMAG signal.
DMAG
57
A9
TI
AL
DMA Grant. This input to the BCRTM allows the BCRTM to access RAM.
It is recognized 45ns before the rising edge of MCLKD2.
DMAGO
67
B5
TO
AL
DMA Grant Out. If DMAG is received but not needed, it passes through
to this output.
DMACK
58
B8
TTO
ZL
DMA Acknowledge. The BCRTM asserts this signal to confirm receipt of
DMAG, it stays low until memory access is complete.
BURST
74
A1
TO
AH
Burst (DMA Cycle). This indicates that the current DMA cycle transfers at
least two words; worst case is five words plus a “dummy” word.
TSCTL
55
B9
TO
AL
Three-State Control. This signal indicates when the BCRTM is actually
accessing memory. The host subsystem’s address and data lines must be
in the high-impedance state when the signals active. This signal assists
in placing the external data and address buffers into the high-impedance
state.
CLOCK SIGNALS
NAME
PIN NUMBER
TYPE
ACTIVE
DESCRIPTION
FP
PGA
CLK
21
J5
TI
--
Clock. The 12MHz input clock requires a 50% ± 10% duty cycle
with an accuracy of ± 0.01%. The accuracy is required in order to
meet the Manchester encoding/decoding requirements of MIL-STD1553B.
MCLK
65
C5
TI
--
Memory Clock. This is the input clock frequency the BCRTM uses
for memory accesses. The memory cycle time is equal to two MCLK
cycles. Therefore, RAM access time is dependent upon the chosen
MCLK frequency (6MHz minimum, 12MHz maximum). Please see
the BCRTM DMA timing diagrams in this chapter.
MCLKD2
71
A3
TO
--
Memory Clock Divided by Two. This signal is the Memory Clock input
divided by two. It assists the host subsystem in synchronizing DMA
events.
POWER AND GROUND
NAME
PIN NUMBER
TYPE
ACTIVE
DESCRIPTION
FP
PGA
VDD
23, 43, 64, 84
L6, F9, C6, ’E3
PWR
--
+5V
VSS
1, 22, 42, 63
F3, J6, F10, B6
GND
--
Ground
36-00-09-000
Revision 1.0.0
10
Cobham Semiconductor Solutions
Cobham.com/HiRel
3.0 INTERNAL REGISTERS
The BCRT’s internal registers (see table 1 on pages 16-17)
enable the CPU to control the actions of the BCRT while
maintaining low DMA overhead by the BCRT. All functions
are active high and ignored when low unless stated
otherwise. Functions and parameters are used in both RT
and BC modes except where indicated. Registers are
addressed by the binary equivalent of their decimal number.
For example, Register 1 is addressed as 0001B. Register
usage is defined as follows:
#0 Control Register
Bit
Number
Description
BITs 15-12 Reserved.
BIT 11
Enable External Override. For use in multi-redundant systems. This bit enables the EXTOVR pin.
BIT 10
BC/RT Select. This function selects between the Bus Controller and Remote Terminal operation modes. It
overrides the external BCRTSEL input setting if the Change Lock-Out function is not used. A reset
operation must be performed when changing between BC and RT modes. This bit is write-only.
BIT 9
(BC) Retry on Alternate Bus. This bit enables an automatic retry to operate on alternate buses. For example, if on
bus A, with two automatic retries programmed, the automatic retries occur on bus B.
BIT 8
(RT) Channel B Enable. When set, this bit enables Channel B operation.
(BC) No significance.
BIT 7
(RT) Channel A Enable. When set, this bit enables Channel A operation.
(BC) Channel Select A/B. When set, this bit selects Channel A.
BITs 6-5
(BC) Retry Count. These bits program the number (1-4) of retries to attempt. (00 = 1 retry,11 = 4 retries)
BIT 4
(BC) Retry on Bus Controller Message Error. This bit enables automatic retries on an error the Bus Controller
detects (see the Bus Controller Architecture section, page 27).
BIT 3
(BC) Retry on Time-Out. This bit enables an automatic retry on a response time-out condition.
BIT 2
(BC) Retry on Message Error. This bit enables an automatic retry when the Message Error bit is set in the RT’s
status word response.
BIT 1
(BC) Retry on Busy. This bit enables automatic retry on a received Busy bit in an RT status word response.
BIT 0
Start Enable. In the BC mode, this bit starts/restarts Command Block execution. In the RT mode, it enables the
BCRT to receive a valid command. RT operation does not start until a valid command is received. When using
this function:
• Restart the BCRT after each Master Reset or programmed reset.
• This bit is not readable; verify operation by reading bit 0 of the BCRT’s Status Register.
36-00-09-000
Revision 1.0.0
11
Cobham Semiconductor Solutions
Cobham.com/HiRel
#1 Status Register (Read Only)
These bits indicate the BCRT’s current status.
Bit
Number
Description
BIT 15
TEST. This bit reflects the inverse of the TEST output. It changes state simultaneously with the TEST output.
BIT 14
(RT) Remote Terminal Active. Indicates that the BCRT, in the Remote Terminal mode, is presently servicing a
command. This bit reflects the inverse of the COMSTR pin.
BIT 13
(RT) Dynamic Bus Control Acceptance. This bit reflects the state of the Dynamic Bus Control Acceptance bit in
the RT status word (see Register 10 on page 15).
BIT 12
(RT) Terminal Flag bit is set in RT status word. This bit reflects the result of writing to Register 10, bit 11.
BIT 11
(RT) Service Request bit is set in RT status word. This bit reflects the result of writing to Register 10, bit 10.
BIT 10
(RT) Busy bit is set in RT status word. This bit reflects the result of writing to Register 10, bits 9 or 14.
BIT 9
BIT is in progress.
BIT 8
Reset is in progress. This bit indicates that either a write to Register 12 has just occurred or the BCRT has just
received a Reset Remote Terminal (#01000) Mode Code. This bit remains set less than one microsecond.
BIT 7
BC/RT Mode. Indicates the current mode of operation. A reset operation must be performed when changing
between BC and RT modes.
BIT 6
Channel A/B. Indicates either the channel presently in use or the last channel used.
BIT 5 Subsystem Fail Indicator. Indicates receiving a subsystem fail signal from the host subsystem on the
SSYSF input.
BITs 4-1
Reserved.
BIT 0
(BC) Command Block Execution is in progress. (RT) Remote Terminal is in operation. This bit reflects bit 0 of
Register 0.
#2 Current Command Block Register (BC)/Remote Terminal Descriptor Space Address Register (RT)
(BC) This register contains the address of the head pointer of the Command Block being executed. Accessing a new
Command Block updates it.
(RT) The host CPU initializes this register to indicate the starting location of the RT Descriptor Space. The host must
allocate 320 sequential locations following this starting address. For proper operation, this location must start on an I x
512 decimal address boundary, where I is an integer multiple. (I = 0 is valid boundary condition.)
#3 Polling Compare Register
In the polling mode, the CPU sets the Polling Compare Register to indicate the RT response word on which the BCRT
should interrupt. This register is 11 bits wide, corresponding to bit times 9 through 19 of the RT’s 1553 status word
response. The sync, Remote Terminal Address, and parity bits are not included (see the section on Polling, page 30).
36-00-09-000
Revision 1.0.0
12
Cobham Semiconductor Solutions
Cobham.com/HiRel
#4 BIT (Built-In-Test) Word Register
The BCRT uses the contents of this register when it responds to the Transmit BIT Word Mode Code (#10011). In addition,
the BCRT writes to the two most significant bits of the BIT Word Register in response to either an Initiate Self-Test Mode
Code (RT mode) or a write to Register 11 (BIT Start Command). If the BIT Word needs to be modified, it can be read out,
modified, then rewritten to this register. Note that if the processor writes a “1” to either bit 14 or 15 of this register, it
effectively induces a BIT failure.
Bit
Number
Description
BIT 15
Channel B. Failure.
BIT 14
Channel A. Failure.
BITs 13-0 BIT Word. The least significant fourteen bits of the BIT Word are user programmable.
#5 Current Command Register (Read Only)
In the RT mode, this register contains the command currently being processed. When not processing a command, the BCRT
stores the last command or status word transmitted on the 1553B bus. This register is updated only when bit 0 of Register
0 is set. In the BC mode, this register contains the most current command sent out on the 1553B bus.
#6 Interrupt Log List Pointer Register
Initialized by the CPU, the Interrupt Log List Pointer Register indicates the start of the Interrupt Log List. After each list
entry, the BCRT updates this register with the address of the next entry in the list. (See page 33.)
#7 High-Priority Interrupt Enable Register (R/W)
Setting the bits in this register causes a High-Priority Interrupt when the enabled event occurs. To service the High-Priority
Interrupt, the user reads Register 8 to determine the cause of the interrupt, then writes to Register 8 to clear the appropriate
bits. The BCRT also provides a Standard Priority Interrupt Scheme that does not require host intervention. If High-Priority
Interrupt service is not possible in a given application, it is advisable to use the Standard Priority features.
Bit
Number
Description
BITs 15-9 Reserved.
BIT 8
Data Overrun Enable. When set, this bit enables an interrupt when DMAG was not received by the BCRT within
the allotted time needed for a successful data transfer to memory.
BIT 7
(BC) Illogical Command Error Enable. This bit enables a High-Priority Interrupt to be asserted upon the
occurrence of an Illogical Command. Illogical commands include incorrectly formated RT-RT Command Blocks.
BIT 6
(RT) Dynamic Bus Control Mode Code Interrupt Enable. When set, the BCRT asserts an interrupt when the
Dynamic Bus Control Mode Code is received.
BIT 5
Subsystem Fail Enable. When set, a High-Priority Interrupt is asserted after receiving a Subsystem Fail (SSYSF)
input pin.
BIT 4
End of BIT Enable. This bit indicates the end of the internal BIT routine.
BIT 3
BIT Word Fail Enable. This bit enables an interrupt indicating that the BCRT detected a BIT failure.
BIT 2
(BC) End of Command Block List Enable (see Command Block Control Word, page 29.) This interrupt can be
superseded by other high-priority interrupts.
BIT 1 Message Error Enable. If enabled, a High-Priority Interrupt is asserted at the occurrence of a message
error. If a High-Priority Interrupt condition occurs, as the result of an enabled message error, the device will
halt operation until the user clears the interrupt by writing a “1” to bit 1 of the High-Priority Interrupt Status/
Reset Register (Reg. #8). If this interrupt is not cleared, the BCRT remains in the HALTED state (appearing to
be “locked-up”), even if it receives a valid message. This High-Priority Interrupt scheme is necessary in order
to maintain the BCRT’s state of operation so that the host CPU has this information available at the time of
interrupt service.
BIT 0
36-00-09-000
Revision 1.0.0
Standard Interrupt Enable. Setting this bit enables the STDINTL pin, but does not cause a high-priority
interrupt. If low, only the STDINTP pin is asserted when a Standard Interrupt occurs.
13
Cobham Semiconductor Solutions
Cobham.com/HiRel
#8 High-Priority Interrupt Status/Reset Register
When a High-Priority Interrupt is asserted, this register indicates the event that caused it. To clear the interrupt signal
and reset the bit, write a “1” to the appropriate bit. See the corresponding bit definitions of Register 7, High-Priority
Interrupt Enable Register.
Bit
Number
Description
BITs 15-9 Reserved.
BIT 8
Data Overrun.
BIT 7
Illogical Command.
BIT 6
Dynamic Bus Control Mode Code Received.
BIT 5
Subsystem Fail.
BIT 4
End of BIT.
BIT 3
BIT Word Fail.
BIT 2
End of Command Block.
BIT 1
Message Error.
BIT 0
Standard Interrupt. The BCRT sets this bit when any Standard Interrupt occurs, providing bit 0 of Register
7 is enabled. (Reset STDINTL output.)
#9 Standard Interrupt Enable Register
This register enables Standard Interrupt logging for any of the following enabled events (Standard Interrupt logging can
also occur for events enabled in the BC Command Block or RT Subaddress/Mode Code Descriptor):
Bit
Number
Description
BITs 15-6 Reserved.
BIT 5
(RT) Illegal Broadcast Command. When set, this bit enables an interrupt indicating that an Illegal
Broadcast Command has been received.
BIT 4
(RT) Illegal Command. When set, this bit enables an interrupt indicating that an illegal command has been
received.
BIT 3
user
(BC) Polling Comparison Match. This enables an interrupt indicating that a polling event has occurred. The
must also set bit 12 in the BC Command Block Control Word for this interrupt to occur.
BIT 2
(BC) Retry Fail. This bit enables an interrupt indicating that all the programmed number of retries have
failed.
BIT 1
(BC, RT) Message Error Event. This bit enables a standard interrupt for message errors.
BIT 0
(BC) Command Block Interrupt and Continue. This bit enables an interrupt indicating that a Command
Block, with the Interrupt and Continue Function enabled, has been executed.
36-00-09-000
Revision 1.0.0
14
Cobham Semiconductor Solutions
Cobham.com/HiRel
#10 Remote Terminal Address Register
This register sets the Remote Terminal Address via software. The Change Lock-Out Enable feature, when set, prevents the
Remote Terminal Address or the BCRT Mode Selection from changing.
Bit
Number
Description
BIT 15
(RT) Instrumentation. Setting this bit sets the RT status word Instrumentation bit.
BIT 14
(RT) Busy. Setting this bit sets the RT status word Busy bit. It does not inhibit data transfers to the subsystem.
BIT 13
(RT) Subsystem Fail. Setting this bit sets the RT status word Subsystem Flag bit. In the RT mode, the
Subsystem Fail is also logged into the Message Status Word.
BIT 12
(RT) Dynamic Bus Control Acceptance. Setting this bit sets the RT status word Dynamic Bus Control
Acceptance bit when the BCRT receives the Dynamic Bus Control Mode Code from the currently active Bus
Controller. Host intervention is required for the BCRT to take over as the active Bus Controller.
BIT 11
(RT) Terminal Flag. Setting this bit sets the RT status word Terminal Flag bit; the Terminal Flag bit in the RT
status word is also internally set if the BIT fails.
BIT 10
(RT) Service Request. Setting this bit sets the RT status word Service Request bit.
BIT 9
(RT) Busy Mode Enable. Setting this bit sets the RT status word Busy bit and inhibits all data transfers to the
subsystem.
BIT 8
BC/RT Mode Select. This bit’s state reflects the external pin BCRTSEL. It does not necessarily reflect the state
of the chip, since the BC/RT Mode Select is software-programmable via bit 10 of Register 0. This bit is read
only.
BIT 7
Change Lock-Out. This bit’s state reflects the external pin LOCK. When set, this bit indicates that changes to
the RT address or the BC/RT Mode Select are not allowed using internal registers. This bit is read-only.
BIT 6
Remote Terminal Address Parity Error. This bit indicates a Remote Terminal Address Parity error. It appears
after the Remote Terminal Address is latched if a parity error exists.
BIT 5
Remote Terminal Address Parity. This is an odd parity input bit used with the Remote Terminal Address. It
ensures accurate recognition of the Remote Terminal Address.
BITs 4-0
Remote Terminal Address (Bit 0 is the LSB). This reflects the RTA4-0 inputs at Master Reset. Modify the
Remote Terminal Address by writing to these bits.
#11 BIT Start Register (Write Only)
Any write (i.e., data = don’t care) to this register’s address location initiates the internal BIT routine, which lasts
100ms. Verify using the BIT-in-progress bit in the Status Register. A programmed reset (write to Register 12) must precede
a write to this register to initiate the internal BIT. A failure of the BIT will be indicated in Register 4 and the BCRTF pin.
The BCRT’s self-test performs an internal wrap around test between its Manchester encoder and its two Manchester decoders.
If the BCRT detects a failure on either the primary or the secondary channel, it flags this failure by setting bit 14 of Register
4 (BIT Word Register) for Channel A and/or bit 15 for Channel B. When in the Remote Terminal mode, while the BCRT is
performing its self-test, it ignores any commands on the 1553 bus until it has completed the self-test.
#12 Programmed Reset Register (Write Only)
Any write (i.e., data = don’t care) to this register’s address location initiates a reset sequence of the encoder/decoder and
protocol sections of the BCRT which lasts less than 1 microsecond. This is identical to the reset used for the Reset Remote
Terminal Mode Code except that command processing halts. For a total reset (i.e., including registers), see the MRST signal
description.
#13 RT Timer Reset Register (Write Only)
Any write (i.e., data = don’t care) to this register’s address location resets the RT Time Tag timer to zero. The BCRT’s Remote
Terminal Timer time-tags message transactions. The time tag is generated from a free-running eight-bit timer of 64
microseconds resolution. This timer can be reset to zero simply by writing to Register 13. When the timer is reset, it
immediately starts running.
36-00-09-000
Revision 1.0.0
15
Cobham Semiconductor Solutions
Cobham.com/HiRel
#0
BC/RT CONTROL REGISTER
15
14
UNUSED
7
CHNSEL
BUSAEN
#1
3
2
1
0
RTYTO
RTYME
RTYBSY
STEN
13
12
11
DYNBUS
RT FLAG
SRQ
10
BUSY
9
8
BIT
RESET
4
3
2
1
0
UNUSED
UNUSED
UNUSED
UNUSED
CMBKPG
(BC) CURRENT COMMAND BLOCK REGISTER
(RT) REMOTE TERMINAL DESCRIPTOR SPACE ADDRESS REGISTER
15
14
13
12
11
10
A14
A13
A12
A11
A10
9
8
A9
A8
7
6
5
4
3
2
1
0
A7
A6
A5
A4
A3
A2
A1
A0
POLLING COMPARE REGISTER
15
14
13
12
11
X
X
X
X
7
6
5
4
3
SWBT12
SWBT13
SWBT14
BRDCST
BUSY
BIT WORD REGISTER
15
14
CHAFAIL
10
MSGERR
2
SS FLAG
13
12
11
10
D13
D12
D11
D10
9
8
INSTR
SRQ
1
0
DBC
RT FLAG
9
8
D9
D8
7
6
5
4
3
2
1
0
D7
D6
D5
D4
D3
D2
D1
D0
CURRENT COMMAND REGISTER
15
14
13
12
11
10
D12
D11
D10
D14
D13
9
8
D9
D8
7
6
5
4
3
2
1
0
D7
D6
D5
D4
D3
D2
D1
D0
INTERRUPT LOG LIST POINTER REGISTER
15
14
13
12
11
10
A11
A10
A14
A13
A12
9
8
A9
A8
7
6
5
4
3
2
1
0
A7
A6
A5
A4
A3
A2
A1
A0
BCRT HIGH-PRIORITY INTERRUPT ENABLE REGISTER
15
14
13
12
UNUSED
7
6
CMDERR
DYNBUS
UNUSED
5
SSFAIL
UNUSED
11
10
9
8
UNUSED
UNUSED
UNUSED
DMAERR
4
3
2
1
0
ENDBIT
BITFAIL
EOL
MSGERR
STDINT
BCRT HIGH-PRIORITY INTERRUPT STATUS/RESET REGISTER
15
14
13
12
11
UNUSED
36-00-09-000
Revision 1.0.0
4
RTYBCME
5
UNUSED
#8
8
BUSBEN
SSFAIL
A15
#7
9
RTYALTB
6
D15
#6
10
BC/RT
BUSA/B
CHBFAIL
#5
RTACT
11
EXTOVR
7
X
#4
5
RTYCNT
12
UNUSED
BC/RT
A15
#3
13
UNUSED
6
BC/RT STATUS REGISTER
15
14
TEST
#2
UNUSED
UNUSED
7
6
ILLCMD
DYNBUS
UNUSED
5
SSFAIL
UNUSED
UNUSED
10
9
8
UNUSED
UNUSED
DATOVR
4
3
2
1
0
ENDBIT
BITFAIL
EOL
MSGERR
STDINT
16
Cobham Semiconductor Solutions
Cobham.com/HiRel
#9
STANDARD INTERRUPT ENABLE REGISTER
15
14
13
12
UNUSED
#10
#12
UNUSED
7
6
5
4
UNUSED
ILLBCMD
ILLCMD
BUSY2
SS FLAG
11
10
9
8
UNUSED
UNUSED
UNUSED
UNUSED
3
REMOTE TERMINAL ADDRESS REGISTER
15
14
13
12
DBC
POLFAIL
2
RTYFAIL
1
0
MSGERR
CMDBLK
11
10
9
8
RT FLAG
SRQ
BUSY1
BC/RT
7
6
5
4
3
2
1
0
LOCK
PARERR
RTAPAR
RTA4
RTA3
RTA2
RTA1
RTA0
8
BUILT-IN-TEST START REGISTER
15
14
13
12
11
10
9
X
X
X
X
X
X
X
X
7
6
5
4
3
2
1
0
X
X
X
X
X
X
X
X
12
11
10
9
8
X
X
X
X
X
PROGRAMMED RESET REGISTER
15
14
13
X
#13
UNUSED
UNUSED
INSTR
#11
UNUSED
X
X
7
6
5
4
3
2
1
0
X
X
X
X
X
X
X
X
REMOTE TERMINAL TIMER RESET REGISTER
15
14
13
12
11
10
9
8
X
X
X
X
X
X
X
X
7
6
5
4
3
2
1
0
X
X
X
X
X
X
X
X
X= DON’T CARE
Table 1. BCRT Registers (continued from page 16)
4.0 SYSTEM OVERVIEW
The BCRT can be configured for a variety of processor and
memory environments. The host processor and the BCRT
communicate via a flexible, programmable interrupt
structure, internal registers, and a user-definable shared
memory area. The shared memory area (up to 64K) is
completely user-programmable and communicates BCRT
control information -- message data, and status/error
information.
from being overwritten by subsequent messages. This
buffering also extends the intervals required by the host
processor to service the data. Selecting an appropriate
MCLK frequency to meet system memory access time
requirements controls the memory access rate. The
completion of a user-defined task or the occurrence of a
user-selected event is indicated by using the extensive set
of interrupts provided.
Built-in memory management functions designed
specifically for MIL-STD-1553B applications aid processor
off-loading. The host needs only to establish the parameters
within memory so the BCRT can access this information as
required. For example, in the RT mode, the BCRT can store
data associated with individual subaddresses anywhere
within its 64K address space. The BCRT then can
automatically buffer up to 128 incoming messages of the
same subaddress, thus preventing the previous messages
In the BC mode, the BCRT can process multiple messages,
assist in scheduling message lists, and provide hostprogrammable functions such as auto retry. The BCRT is
incorporated in systems with a variety of interrupt latencies
by using the Interrupt History List feature (see Exception
Handling and Interrupt Logging, page 33). The Interrupt
History List sequentially stores the events that caused the
interrupt in memory without losing information if a host
processor does not respond immediately to an interrupt.
36-00-09-000
Revision 1.0.0
17
Cobham Semiconductor Solutions
Cobham.com/HiRel
5.0 SYSTEM INTERFACE
5.3 CPU Interconnection
5.1 DMA Transfers
The BCRT initiates DMA transfers whenever it executes
command blocks (BC mode) or services commands (RT
mode). DMAR initiates the transfer and is terminated by
the inactive edge of DMACK. The Address Enable (AEN)
input enables the BCRT to output an address onto the
Address bus.
Pseudo-Dual-Port RAM Configuration
The BCRT’s Address and Data buses connect directly to
RAM, with buffers isolating the BCRT’s buses from those
of the host CPU (figures 3a and 3b). The CPU’s memory
control signals (RD, WR, and MEMCSI) pass through the
BCRT and connect to memory as RRL, RWR,
and MEMCSO.
The BCRT requests transfer cycles by asserting the DMAR
output, and initiates them when a DMAG input is received.
A DMACK output indicates
that the BCRT has control of the Data and Address buses.
The TSCTL output is asserted when the BCRT is actually
asserting the Address and Data buses.
RAM
To support using multiple bus masters in a system, the
BCRT outputs the DMAGO signal that results from the
DMAG signal passing through the chip when a BCRT bus
request was not generated (DMAR inactive). You can use
DMAGO in daisy-chained multimaster systems.
CPU MEMORY
CONTROL SIGNALS
RRD
BCRT
RD
RWR
5.2 Hardware Interface
The BCRT provides a simple subsystem interface and
facilitates DMA arbitration. The user can configure the
BCRT to operate in a variety of memory-processor
environments including the pseudo-dual-port RAM and
standard DMA configurations.
WR
MEMCSO
MEMCSI
Figure 3a. Pseudo Dual-Port RAM
Control Signals
For complete circuit description, such as arbitration logic
and I/O, please refer to the appropriate application note.
BUFFERS
16 DATA
RAM
HOST
CPU
16 ADDRESS
CONTROL
BCRT
(DUAL REDUNDANT)
DUAL
TRANSCEIVER
XFMR
CONTROL/ARBITRATION
TRANSMITTER
TIMEOUT
XFMR
BUS A
1553 BUS
BUS B
Figure 3b. CPU/BCRT Interface -- Pseudo-Dual-Port RAM Configuration
36-00-09-000
Revision 1.0.0
18
Cobham Semiconductor Solutions
Cobham.com/HiRel
ADDRESS BUS
DMAR
DMAG
CPU
DMACK
BCRT
DATA BUS
RRD RWR
SHARED
MEMORY
AREA
OE
•
WE
•
CS
•
MEMCSO
Figure 3c. DMA Signals
Standard DMA Configuration
The designer can use TSCTL to indicate when the BCRT is
accessing memory. AEN is also available (use is optional),
giving the CPU control over the BCRT’s Address bus. A DMA
Burst (BURST) signal indicates multiple
DMA accesses.
The BCRT’s and CPU’s data, address, and control signals
are connected to each other as shown in figures 3c and 3d.
The RWR, RRL, and MEMCSO are activated after DMAG is
asserted.
Register Access
In either case, the BCRT’s Address and Data buses remain
in a high-impedance state unless the CS and RD signals are
active, indicating a host register access; or TSCTL is
asserted, indicating a memory access by the BCRT. CPU
attempts to access BCRT registers are ignored during BCRT
memory access. Inhibit DMA transfers by using the Busy
function in the Remote Terminal Address Register while
operating in the Remote Terminal mode.
Registers 0 through 13 are accessed with the decode of the
four LSBs of the Address bus (A0-A3) and asserting CS.
Pulse either RD or WR for multiple register accesses.
RAM
DATA
BCRT
ADDRESS
MEMORY
BUFFER
CONTROL
CPU
ARBITRATION
DUAL
TRANSCEIVER
XFMR
XFMR
BUS A
1553 BUS
BUS B
Figure 3d. CPU/BCRT Interface -- DMA Configuration
36-00-09-000
Revision 1.0.0
19
Cobham Semiconductor Solutions
Cobham.com/HiRel
5.4 RAM Interface
The BCRT’s RRD, RWR, and MEMCSO signals serve as read
and write controls during BCRT memory accesses. The
host subsystem signals RD, WR, and MEMCSI propagate
through the BCRT to become RRD, RWR, and MEMCSO
outputs to support a pseudo-dual-port. During BCRT-RAM
data transfers, the host subsystem’s memory signals are
ignored until the BCRT access is complete.
BCRT
TIMERON
CHANNEL A
CHANNEL A
TXINHA
CHANNEL B CHA/B
5.5 Transmitter/Receiver Interface
The BCRT’s Manchester II encoder/decoder interfaces
directly with the 1553 bus transceiver, using the TAO-TAZ
and RAZ-RAO signals for Channel A, and TBO-TBZ and
RBZ-RBO signals for Channel B.
CHANNEL B
DUAL
TRANSCEIVER
TXINHB
Figure 4. Dual-Channel Transceiver
36-00-09-000
Revision 1.0.0
20
Cobham Semiconductor Solutions
Cobham.com/HiRel
6.0 REMOTE TERMINAL ARCHITECTURE
The Remote Terminal architecture is a descriptorbased configuration of relevant parameters. It is composed
of an RT Descriptor Space (see figure 5) and internal, hostprogrammable registers. The Descriptor Space contains
only descriptors. Descriptors contain programmable
subaddress parameters relating to handling message
transfers. Each descriptor consists of four words: (1) a
Control Word, (2) a Message Status List Pointer, (3) a Data
List Pointer, and (4) an unused fourth word (see figure 6.)
These words indicate how to perform the data transfers
associated with the designated subaddress.
Each descriptor contains a programmable interrupt
structure for subsystem notification of user-selected
message transfers and indicates when the message buffers
are full. Illegalizing subaddresses, in normal and broadcast
modes, is accomplished by using programmable bits within
the descriptor (see the RT Functional Operation section on
next page).
Message Status information -- including word count, an
internally generated time tag, and broadcast and message
validity information -- is provided for each message. The
Message Status Words are stored in a separate Message
Status Word list according to subaddress. The list’s starting
locations are programmable within the descriptor.
A receive descriptor and a transmit descriptor are
associated with each subaddress. The descriptors reside in
memory and are listed sequentially by subaddress. By using
the index within the descriptor, the BCRT can buffer
incoming and outgoing messages, which reduces host CPU
overhead. This message buffering also reduces the risk of
incoming messages being overwritten by subsequent
incoming messages.
- STARTING ADDRESS
INITIALIZED BY CPU
IN THE RT DESCRIPTOR
SPACE REGISTER
RECEIVE
SUBADDRESS #1
RECEIVE
SUBADDRESS #2
RECEIVE
SUBADDRESS #30
Message data, received or transmitted, is also stored in lists.
The message capacity of the lists and the lists’ locations are
user selectable within the descriptor.
6.1 RT Functional Operation
The RT off-loads the host computer of all routine data
transfers involved with message transfers over the 1553B
bus by providing a wide range of user-programmable
functions. These functions make the BCRT’s operation
flexible for a variety of applications. The following
paragraphs give each function’s operational descriptions.
6.1.1 RT Subaddress Descriptor Definition
The host sets words within the descriptor. The BCRT then
reads the descriptor words when servicing a command
corresponding to the specified descriptor. All bit-selectable
functions are active high and inhibited when low.
UNUSED
UNUSED
TRANSMIT
SUBADDRESS #1
TRANSMIT
SUBADDRESS #2
ILLEGAL BROADCAST
SUBADDRESS
ILLEGAL
SUBADDRESS
INTERRUPT WHEN
ADDRESSED
TRANSMIT
SUBADDRESS #30
INTERRUPT WHEN
INDEX = 0
UNUSED
15
UNUSED
UNUSED
10
9
8
7
I
I
I
I
MODE CODE
#’s 0 & 16
MESSAGE STATUS LIST POINTER
MODE CODE
#’s 1 & 17
DATA LIST POINTER
6
0
INDEX
FOR FUTURE EXPANSION
MODE CODE
#’s 15 & 31
Figure 6. Remote Terminal Subaddress
Descriptor
Figure 5. Descriptor Space
36-00-09-000
Revision 1.0.0
21
Cobham Semiconductor Solutions
Cobham.com/HiRel
A. Control Word. The first word in the descriptor, the Control Word, selects or disables message transfers and selects
an index.
Bit
Number
Description
BITs 15-11 Reserved.
BIT 10
Illegal Broadcast Subaddress. Indicates to the BCRT not to access this subaddress using broadcast commands.
The Message Error bit in the status word is set if the illegal broadcast subaddress is addressed. Since transmit
commands do not apply to broadcast, this bit applies only to receive commands.
BIT 9
Illegal Subaddress. Set by the host CPU, it indicates to the BCRT that a command with this subaddress is illegal.
If a command uses an illegal subaddress the Message Error bit in the 1553 status word is set. The Illegal
Command Interrupt is also asserted if enabled.
BIT 8
Interrupt Upon Valid Command Received. Indicates that the BCRT is to assert an interrupt every time a
command addresses this descriptor. The interrupt occurs just prior to post-command descriptor updating.
BIT 7
Interrupt When Index = 0. Indicates that the BCRT initiates an interrupt when the index is decremented to
zero.
BITs 6-0
Index. These bits are for indexed message buffering. Indexing means transacting a pre-specified number of
messages before notifying the host CPU. After each message transaction, the BCRT decrements the index
by one until index = 0. Note that the index is decremented for messages that contain message errors.
B. Message Status List Pointer. The host sets the Message Status List Pointer, the second word within the descriptor,
and the BCRT uses it as a starting address for the Message Status List. It is incremented by one with each Message
status word write. If the Control Word Index is already equal to zero, the Message Status List Pointer is not incremented
and the previous Message status word is overwritten.
Note: A Message Status Word is also written and the pointer is incremented when the BCRT detects a message error.
C. Data List Pointer. The Data List Pointer is the third word within the descriptor. The BCRT stores data in RAM
beginning at the address indicated by the Data List Pointer. The Data List Pointer is updated at the end of each successful
message with the next message’s starting address with the following exceptions:
• If the message is erroneous, the Data List Pointer is not updated. The next message overwrites any data
corresponding to the erroneous message.
• Upon receiving a message, if the index is already equal to zero, the Data List Pointer is not
incremented and data from the previous message is overwritten.
D. Reserved. The fourth descriptor word is reserved for future use.
36-00-09-000
Revision 1.0.0
22
Cobham Semiconductor Solutions
Cobham.com/HiRel
6.1.2 Message Status Word
15
Each message the BCRT transacts has a corresponding
Message Status Word, which is pointed to by the Message
Status List Pointer of the Descriptor. This word allows the
host CPU to evaluate the message’s validity, determine the
word count, and calculate the approximate time frame in
which the message was transacted (figures 7 and 8).
14
13
12
8
WORD COUNT
7
0
TIME TAG
MESSAGE ERROR
MESSAGE WAS BROADCASTED
SUBSYSTEM FAIL INPUT WAS
ASSERTED DURING THIS MESSAGE
Figure 7. Message Status Word
MESSAGE STATUS WORD
LIST
DATA LIST
MESSAGE
#1
#1
MESSAGE
#2
#3
MESSAGE
#3
MESSAGE
#4
#2
#4
MESSAGE STATUS
LIST POINTER
#5
DATA LIST
POINTER
(FROM RT DESCRIPTOR)
MESSAGE
#5
Figure 8. Remote Terminal Data and Message Status List
Message Status Word Definition
Bit
Number
Description
BIT 15
Subsystem Failed. Indicates SSYSF was asserted before the Message Status Word transfer to memory. This bit
is also set when the user sets bit 13 of Register 10.
BIT 14
Broadcast Message. Indicates that the corresponding message was received in the broadcast mode.
BIT 13
Message Error. Indicates a message is invalid due to improper synchronization, bit count, word count,
Manchester error.
BITs 12-8 Word Count. Indicates the number of words in the message and reflects the Word Count field in the command
word. Should the message contain a different number of words than the Word Count field, the Message Error flag
is triggered. If there are too many words, they are withheld from RAM. If the actual word count is less than or
greater than it should be, the Message Error bit in the 1553 status word is set.
BITs 7-0
36-00-09-000
Revision 1.0.0
Time Tag. The BCRT writes the internally generated Time Tag to this location after message completion. The
resolution is 64 microseconds. (See Register 13). If the timer reads 2, it indicates the message was completed 128
to 191 microseconds after the timer started.
23
Cobham Semiconductor Solutions
Cobham.com/HiRel
6.1.3 Mode Code Descriptor Definition
Mode codes are handled similarly to subaddress
transactions. Both use the four-word descriptors residing
in the RT descriptor space to allow the host to program
their operational mode. Corresponding to each mode code
is a descriptor (see figure 9a). Of the 32 address
combinations for mode codes in MIL-STD-1553B, some
are clearly defined functions while others are reserved for
future use. Sixteen descriptors are used for mode code
operations with each descriptor handling two mode codes:
one mode code with an associated data word and one
mode code without an associated data word. All mode
codes are handled in accordance with MIL-STD-1553B.
The function of the first word of the Mode Code Descriptor
is similar to that of the Subaddress Descriptor and is
defined below. The remaining three words serve the same
purpose as in the Subaddress Descriptor.
REMOTE TERMINAL
DESCRIPTOR SPACE
STARTING ADDRESS
(RTDSSA) + 256
MODE CODE
#’S 0 & 16
MODE CODE
#’S 1 & 17
MODE CODE
#’S 2 & 18
MODE CODE
#’S 15 & 31
RTDSSA + 320
Note:
Mode code descriptor blocks are also provided for reserved
mode codes but have no associated predefined BCRTM
operation.
Figure 9a. (RT) Mode Code Descriptor Space
Control Word
Bit
Number
Description
BIT 15
Interrupt on Reception of Mode Code (without Data Word).
BIT 14
Illegalize Broadcast Mode Code (without Data Word).
BIT 13
Illegalize Mode Code (without Data Word).
BIT 12
Reserved.
BIT 11
Illegalize Broadcast Mode Code (with Data Word).
BIT 10
Illegalize Transmit Mode Code (with Data Word).
BIT 9
Illegalize Receive Mode Code (with Data Word).
BIT 8
Interrupt on Reception of Mode Code (with Data Word).
BIT 7
Interrupt if Index = 0.
BITs 6-0
Index. Functionally equivalent to the index described in the Subaddress Descriptor. It applies to mode codes
with data words only.
INTERRUPT ON RECEPTION OF MODE CODE
(WITHOUT DATA WORD)
ILLEGALIZE BROADCAST MODE CODE
(WITHOUT DATA WORD)
ILLEGALIZE MODE CODE
(WITHOUT DATA WORD)
RESERVED
ILLEGALIZE BROADCAST MODE CODE
(WITH DATA WORD)
ILLEGALIZE TRANSMIT MODE CODE
(WITH DATA WORD)
15
14
13
12
11
10
9
8
MESSAGE STATUS LIST POINTER
DATA LIST POINTER
RESERVED
7
ILLEGALIZE RECEIVE MODE CODE
(WITH DATA WORD)
INTERRUPT ON RECEPTION OF MODE CODE
(WITH DATA WORD)
INTERRUPT IF INDEX = 0
6
INDEX
0
Figure 9b. (RT) Mode Code Descriptor
36-00-09-000
Revision 1.0.0
24
Cobham Semiconductor Solutions
Cobham.com/HiRel
Override Inhibit Terminal Flag Bit #00111
The descriptors, numbered sequentially from 0 to 15,
correspond to mode codes 0 to 15 without data words and
mode codes 16 to 31 with data words. For example, mode
codes 0 and 16 correspond to descriptor 0 and mode codes
1 and 17 correspond to descriptor 1. The Mode Code
Descriptor Space is appended to the Subaddress Descriptor
Space starting at 0100H (256D) of the 320-word RT
Descriptor Space (see figure 5).
The BCRT disables the Terminal Flag inhibit.
Reset Remote Terminal #01000
The BCRT automatically resets the encoder, decoders, and
protocol logic.
Transmit Vector Word #10000
The BCRT autonomously supports all mode codes without
data words by executing the specific function and
transmitting the 1553 status word. The subsystem provides
the data word for mode codes with data words (see the
Data List Pointer section). For all mode codes, an interrupt
can be asserted upon successful completion of the mode
command by setting the appropriate bit in the control word
(see figure 9b).
The BCRT transmits the vector word from the location
addressed by the Data List Pointer in the Mode Code
Descriptor Block.
Synchronize (with Data Word) #10001
On receiving this mode code, the BCRT simply stores the
associated data word.
Dynamic Bus Control #00000
Transmit Last Command #10010
This mode code is accepted automatically if the Dynamic
Bus Control Enable bit in the Remote Terminal Address
Register is set. Setting the Dynamic
Bus Control Acceptance bit in the 1553 status word and
BCRT Status Register confirms the mode code acceptance.
A High-Priority Interrupt is also asserted if enabled. If the
Dynamic Bus Control Enable bit is not set, the BCRT does
not accept Dynamic Bus Control.
The BCRT transmits the last command executed and the
corresponding 1553 status word.
Synchronize (Without Data Word) #00001
On receiving this mode code, the BCRT simply stores the
associated data word.
Transmit BIT Word #10011
The BCRT transmits BIT information from the BIT
Register.
Selected Transmitter Shutdown #10100
If enabled in the Mode Code #00001 Descriptor Control
Word, the BCRT asserts an interrupt when this mode code
is received.
Override Selected Transmitter Shutdown #10101
On receiving this mode code, the BCRT simply stores the
associated data word.
Transmit Status Word #00010
Mode codes 9-15 and 22-31 are reserved for future
expansion of MIL-STD-1553B.
The BCRT automatically transmits the 1553 status word
corresponding to the last message transacted.
Initiate Self-Test #00011
The BCRT automatically starts its BIT routine. An interrupt,
if enabled, is asserted when the test is completed. The BIT
Word Register and external pin BCRTF are updated when
the test is completed. A failure in BIT will also set the TF
status word bit.
Transmitter Shutdown #00100
The BCRT disables the channel opposite the channel on
which the command was received.
Override Transmitter Shutdown #00101
The BCRT enables the channel previously disabled.
Inhibit Terminal Flag Bit #00110
The BCRT inhibits the Terminal Flag from being set in the
status word.
36-00-09-000
Revision 1.0.0
25
Cobham Semiconductor Solutions
Cobham.com/HiRel
6.2 RT Error Detection
In accordance with MIL-STD-1553B, the remote terminal
handles superseding commands on the same or opposite
bus. When receiving, the remote terminal performs a
response time-out function of 56 microseconds for RT-RT
transfers. If the response time-out condition occurs, a
Message Error bit is set in the 1553 status word and in
the Message Status Word. Error checking occurs on both
of the Manchester logic and the word formats. Detectable
errors include word count errors, long words, short words,
Manchester errors (including zero crossing deviation),
parity errors, and
data discontiguity.
Exception Handling.
If an interrupting condition occurs during the message, the following
occurs:
For High-Priority Interrupts:
HPINT is asserted (if enabled in Register 7). For message
errors, the BCRT is put in a hold state until the interrupt is
acknowledged (by writing a “1” to the appropriate bit in
Register 8).
For Standard Interrupts:
DMA arbitration (BURST)
Interrupt Status Word write
RT Descriptor Block Pointer write
Tail Pointer read (into Register 6)
STDINTP pulses low
STDINTL asserted (if enabled)
Processing continues
6.3 RT Operational Sequence
The following is a general description of the typical
behavior of the BCRT as it processes a message in the RT
mode. It is assumed that the user has already written a
“1” to Register 0, bit 0, enabling RT operation.
•
After the BCRT processes the message, a final DMA burst occurs to
update the descriptor block, if necessary:
Valid Command Received.
DMA arbitration (BURST)
Message Status Word write
Data List Pointer write(incremented by word count)
Message Status List Pointer write (incremented by 1)
Control Word write(index decremented)
COMSTR goes active
•
DMA Descriptor Read. After receiving a valid command, the
BCRT initiates a burst DMA:
Note the following exceptions:
DMA arbitration (BURST)
Control Word read
Message Status List Pointer read
Data List Pointer read
Mode codes without data require no descriptor update.
Predefined mode codes (18 and 19) which do not require access
to memory for the data word, do not involve updating the Data
List Pointer.
Data Transmitted/Received.
•
Descriptor Write.
Messages with errors prevent updates to the Data List Pointer.
Data Word DMA.
If the message index was zero, neither the Message Status List
Pointer nor the Data
List Pointer is updated.
If the BCRT needs to transmit data from memory, it initiates a
DMA cycle for each Data Word shortly before the Data Word is
needed on the 1553B bus:
DMA arbitration
Data Word read (starting at Data List Pointer address,
incremented for each successive word)
If the BCRT receives data, it writes each Data Word to memory
after the Data Word is received:
DMA arbitration
Data Word write (starting at Data List Pointer address,
incremented for each successive word)
Status Word Transmission.
The BCRT automatically transmits the Status Word as defined
in MIL-STD-1553B. The Message Error and Broadcast Command
Received bits are generated internally. Writing to Register 10
enables the other predefined bits. For illegalized commands, the
BCRT sets the Message Error Bit in the 1553 Status Word.
36-00-09-000
Revision 1.0.0
26
Cobham Semiconductor Solutions
Cobham.com/HiRel
7.0 BUS CONTROLLER ARCHITECTURE
A programmable auto retry function is selectable from the
control word and Control Register.
The BCRT’s bus controller architecture is based on a
Command Block structure and internal, hostprogrammable registers. Each message transacted over the
MIL-STD-1553B bus has an associated Command Block,
which the CPU sets up (see figures 10 and 11). The
Command Block contains all the relevant message and RT
status information as well as programmable function bits
that allow the user to select functions and interrupts. This
memory interface system is flexible due to a doubly-linked
list data structure.
The auto retry can be activated when any of the following
occurs:
CONTROL WORD
COMMAND WORD 1
•
Message Error (indicated by the RT status response)
•
Response Time-Out
•
Message Error detected by the Bus Controller
The Bus Controller also has a programmable intermessage
delay timer that facilitates message transfer scheduling (see
figures 13 and 14). This timer, programmed in the control
word, automatically delays between the start of two
successive commands.
COMMAND WORD 2 (RT-RT ONLY)
DATA LIST POINTER
STATUS WORD 1
STATUS WORD 2 (RT-RT ONLY)
A polling function is also provided. The Bus Controller, when
programmed, compares incoming status words to a hostspecified status word and generates an interrupt if the
comparison indicates any matching bits. An Interrupt and
Continue function facilitates the host subsystem’s
synchronization by generating an interrupt when the
specified Command Block’s message is executed.
TAIL POINTER
Figure 10. Command Block
In a doubly-linked Command Block structure, pointers
delimit each Command Block to the previous and successive
blocks (see figure 12). The linking feature eases multiple
message processing tasks and supports message
scheduling because of its ability to loop through a series of
transfers at a predetermined cycle time. A data pointer in
the command allows efficient space allocation because data
blocks only have to be configured to the exact word count
used in the message. Data pointers also provide flexibility in
data-bank switching.
COMMAND BLOCK #1
HP
TP
#2
HP
TP
COMMAND BLOCK
DATA WORD #1
DATA WORD #2
#3
HP
X
LAST DATA WORD
TP
X IS BETWEEN 1 & 32
#4
Figure 11. Data Placement
HP
A control word with bit-programmable functions and a
Message Error bit are in each Command Block. This allows
selecting individual functions for each message and
provides message validity information. The BCRT’s register
set provides additional global parameters and address
pointers.
36-00-09-000
Revision 1.0.0
Busy bit set in the status word
One to four retries are programmable on the same or
opposite bus.
HEAD POINTER
DATA LIST POINTER
•
TP
Figure 12. Command Block
Chaining
27
Cobham Semiconductor Solutions
Cobham.com/HiRel
Command Block register with the next Command Block
Address. The BCRT then executes the sequential
7.1 BC Functional Operation
The Bus Controller off-loads the host computer of many
functions needed to coordinate 1553B bus data transfers.
Special architectural features provide message-bymessage flexibility. In addition, a programmable interrupt
scheme, programmable intermessage timing delays, and
internal registers enhance the BCRT’s operation.
Command Blocks and counts out message delays (where
programmed) until it encounters the last Command Block
listed (indicated by the End of List bit in the control word).
Interrupts are asserted when enabled events occur (see
the Exception Handling and Interrupt Logging section,
page 33).
The host determines the first Command Block by setting
the initial starting address in the current Command Block
Register. Once set, the BCRT updates the current
15
MESSAGE
ERROR
14
SKIP
13
INTERRUPT
AND
CONTINUE
The functions and their programming instructions are
described below. The registers also contain many
programmable functions and function parameters.
12
11
10
POLLING
ENABLE
AUTO
RETRY
ENABLE
END
OF
LIST
9
8
RT-RT
TRANSFER
MONITOR
RT-RT
TRANSFER
7
0
‘TIME DELAY’
Figure 13. Control Word
MESSAGE #1
MESSAGE #2
TDELAY1
MESSAGE #3
TDELAY2
Figure 14. BC Timing Delays
36-00-09-000
Revision 1.0.0
28
Cobham Semiconductor Solutions
Cobham.com/HiRel
BC Command Block Definition
Each Command Block contains (see figure 10):
A.
Head Pointer. Host-written, this location can contain the address of the previous Command Block’s Head Pointer.
The BCRT does not access this location.
B.
Control Word. Host-written, the Control Word contains bit-selectable options and a Message Error bit the BCRT
provides (see figure 13). The bit definitions follow.
Bit
NumberDescription
BIT 15
Message Error. The BCRT sets this bit when it detects an invalid RT response as defined in MIL-STD-1553B.
BIT 14
Skip. When set, this bit instructs the BCRT to skip this Command Block and execute the next.
BIT 13
Interrupt and Continue. If set, a Standard Interrupt is asserted when this block is addressed; operation, however,
continues. Note that this interrupt must also be enabled by setting bit 0 of Register 9.
BIT 12
Polling Enable. Enables the BCRT’s polling operation.
BIT 11
Auto Retry Enable. When set, the Auto Retry function, governed by the global parameters in the Control Register,
is enabled for this message.
BIT 10
End of List. Set by the CPU, this bit indicates that the BCRT, upon completion of the current message, will halt and
assert a High-Priority Interrupt. The interrupt must also be enabled in the High-Priority Interrupt Enable Register.
BIT 9
RT-RT. Set by the CPU, this indicates that this Command Block transacts an RT-RT transfer.
BIT 8
Monitor RT-RT Transfer. Set by the CPU, this function indicates that the BCRT should receive and store the message
beginning at the location indicated by the data pointer.
BITs 7-0 Time Delay. The CPU sets this field, which causes the BCRT to delay the specified time between sequential message
starts (see figures 13 and 14). Regardless of the value in the Time Delay field (including zero), the BCRT will at least
meet the minimum 4ms intermessage gap time as specified in MIL-STD-1553B. The timer is enabled by having a
non-zero value in this bit field. When using this function, please note:
• Timer resolution is16 microseconds. As an example, if a given message requires 116μs tocomplete
(including the minimum 4μs intermessage gap time) the value in the Time Delay field must be at least
00001000 (8 x 16μs = 128μs) to provide an intermessage gap greater than the4μs minimum requirement.
• If the timer is enabled and the Skip bit is set, the timer provides the programmed delay before proceeding.
• If the message duration exceeds the timer delay, the message is completed just as if the timer were not
enabled.
• If SKIP = 1 and EOL = 1, the HPINT is generated if enabled.
• If SKIP = 1 and Interrupt and Continue = 1, the STDINT is generated if enabled.
C.
Command Word One. Initialized by the CPU, this location contains the first command word corresponding to
the Command Block’s message transfer.
D.
Command Word Two. Initialized by the CPU, this location is for the second (transmit) command word in RT-RT
transfers. In messages involving only one RT, the location is unused.
E.
Data Pointer. Initialized by the CPU, this location contains the starting location in RAM for the Command Block’s
message (see figure 15).
F.
Status Word One. Stored by the BCRT, this location contains the entire Remote Terminal status response.
G.
Status Word Two. Stored by the BCRT, this location contains the receiving Remote Terminal status word. For
transfers involving one Remote Terminal, the location is unused.
H.
Tail Pointer. Initialized by the host CPU, the Tail Pointer contains the next Command Block’s starting address.
36-00-09-000
Revision 1.0.0
29
Cobham Semiconductor Solutions
Cobham.com/HiRel
COMMAND BLOCK #1
RAM
RT
DATA POINTER
MESSAGE #1
COMMAND BLOCK #2
MESSAGE #2
DATA POINTER
DATA WORD #1
DATA WORD #2
DATA WORD #3
RESPONSE
DATA WORD #1
DATA WORD #2
DATA WORD #3
DATA WORD #4
Q?
BC
Figure 15. Continuous Data Storage
POLLING RESPONSE REGISTER
(RT STATUS WORD)
7.2 Polling
During a typical polling scenario (see figure 16) the Bus
Controller interrogates remote terminals by requesting
them to transmit their status words. This feature can also
alert the host if a bit is set in any RT status word response
during normal message transactions. The BCRT enables
the host to initialize a chain of Command Blocks with the
command word’s Polling Enable bit. A programmable
Polling Compare Register (PCR) is provided. In the polling
mode, the Remote Terminal response is compared to the
Polling Compare Register contents. Program the PCR by
setting the PCR bits corresponding to the RT’s 1553 status
word bits to be compared. If they match (i.e., two 1’s in
the same bit position) then, if enabled in both the BC
Command Block Control Word and in the Standard
Interrupt Enable Register (Register 9), a polling
comparison interrupt is generated.
POLLING COMPARE WORD
(SET BY CPU)
Figure 16. Polling Operation
7.4 Bus Controller Operational Sequence
The following is a general description of the typical
behavior of the BCRT as it processes a message in the
BC mode.
The user starts BC operation by writing a “1” to Register 0, Bit 0.
•
Command Block DMA - the following occurs immediately after
Bus Controller startup:
DMA arbitration (BURST)
Control Word read
Command Word 1 read (from third location of Command
Block)
Data List Pointer read
Example 1. No bit match is present
A. For BC-to-RT Command Blocks:
PCR
00000000001
RT’s 1553 Status Word response
00000100010
Result
No Polling Comparison Interrupt
The BCRT transmits the Command Word.
•
Example 2. Bit match is present
Data Word DMA
DMA arbitration
Data Word read (starting at Data List Pointer address,
incremented for each successive word)
PCR
00100100000
RT’s 1553 Status Word response
00000100000
Result
Polling Comparison Interrupt
The BCRT transmits the Data Word. Data Word DMAs and
transmissions continue until all Data Words are transmitted.
7.3 BC Error Detection
The Bus Controller checks for errors (see the Exception
Handling and Interrupt Logging and the RT Error
Detection sections, pages 33 and 26) on each message
transaction. In addition, the BC compares the RT
command word addresses to the incoming status word
addresses. The BC monitors for response time-out and
checks data and control words for proper format according
to MIL-STD-1553B. Illogical commands include incorrectly
formatted RT-RT Command Blocks.
36-00-09-000
Revision 1.0.0
RT
RT
•
Status Word DMA
The BCRT receives the RT Status Word.
DMA arbitration
Status Word write (to sixth location of Command Block)
30
Cobham Semiconductor Solutions
Cobham.com/HiRel
Exception Handling.
B. For RT-to-BC Command Blocks:
The BCRT transmits the Command Word.
•
If an interrupting condition occurs during the message, the
following occurs:
Status Word DMA
For High-Priority Interrupts:
The BCRT receives the RT Status Word.
DMA arbitration
Status Word write (to sixth location of Command Block)
HPINT is asserted (if enabled in Register 7). For message
errors, the BCRT is put in a hold state until the interrupt is
acknowledged (by writing a “1” to the appropriate bit in
Register 8).
The BCRT receives the first Data Word.
•
Data Word DMA
For Standard Interrupts:
DMA arbitration
Data Word write (starting at Data List
Pointer address,
incremented for each
successive word)
DMA arbitration (BURST)
Interrupt Status Word write
Command Block Pointer write
Tail Pointer read (into Register 6)
STDINTP pulses low
STDINTL asserted (if enabled)
Processing continues
Data Word receptions and DMAs continue until all Data Words are
received.
C. For RT(B)-to-RT(A) Command Blocks:
The BCRT transmits Command Word 1 to RT(B).
•
If Retries are enabled and a Retry condition occurs, the
following DMA occurs:
Command Word 2 DMA
DMA arbitration
Command Word 2 read (from fourth location of Command
Block)
DMA arbitration (BURST)
Control Word read
Command Word 1 read (from third location of Command
Block)
Data List Pointer read
The BCRT transmits Command Word 2 to RT(A).
The BCRT receives the RT Status Word from RT(A).
•
The BCRT proceeds from the current Command Block to the next
successive Command Block.
Status Word DMA for RT(A) Status Word
DMA arbitration
Status Word write (to sixth location of Command Block)
•
The BCRT receives the first Data Word
•
DMA arbitration (BURST)
Command Block Tail Pointer read (to determine location of
next Command Block. Note that this occurs only if no Retry.)
DMA hold cycle
Control Word read (next Command Block)
Command Word 1 read (next Command Block)
Data List Pointer read
Data Word DMA (only if the BCRT is enabled to monitor the RTto-RT message).
DMA arbitration
Data Word write (starting at Data List Pointer address,
incremented for each successive word)
Data Word receptions and DMAs continue until all Data Words are
received.
•
The BCRT receives the RT Status Word from RT(B).
•
If no Message Error has occurred during the current Command
Block, the following occurs:
If the BCRT detects a Message Error while processing the
current Command Block, the following occurs:
DMA arbitration (BURST)
Control Word write
Command Block Tail Pointer read (to determine location of
next Command Block. Note that this occurs only if no Retry.)
DMA hold cycle
Control Word read (next Command Block)
Command Word 1 read (next Command Block)
Data List Pointer read
Status Word DMA for RT(B) Status Word
DMA arbitration
Status Word write (to seventh location of Command Block)
The BCRT proceeds again from point A, B, or C as
shown above.
36-00-09-000
Revision 1.0.0
31
Cobham Semiconductor Solutions
Cobham.com/HiRel
7.5 BC Operational Example
(see figure 18 on page 35)
The BCRT is programmed initially to accomplish the
following:
D. The BCRT receives the status word response from
the receiving RT. The ME bit in the status word is set,
indicating the message is invalid. The BCRT initiates
the auto retry function, (as programmed) on the
alternate bus, re-transmits the command words,
receives the correct status word, and stores the data
again in locations 0400H - 0403H. This time the status
word response from the receiving RT indicates the
message transfer is successful.
The first Command Block is for a four-word RT-RT transfer
with the BCRT monitoring the transfer and storing the
data.
• Auto-retry is enabled on the opposite bus using only
one retry attempt, if the incoming Status Word is
received with the Message Error bit set.
E. The timer delay between the two successive
transactions counts down another 135 microseconds
before proceeding. This is determined as follows:
• Wait for a time delay of 400ms before proceeding to
the next Command Block.
• The Data List Pointer contains the address 0400H.
The message transaction time is approximately 130
microseconds (the only approximation is due to the
range in status response and intermessage gap
times specified by MIL-STD-1553B). Approximating
that with the retry, the total duration for the two
attempts
is 265ms.
The second Command Block is for a BC-RT transfer of
two words.
• The End of List bit is set in its Control Word.
• The Data List Pointer contains the address 0404H.
• The Polling Enable bit is set and the Polling Compare
Register contains a one in the Subsystem Fail
position (bit 2).
F. The BCRT reads the Tail Pointer of Command Block 1
and places it in the Current Command Register. It
also reads the control word, command word, and
Data List Pointer, and the first data word in the second
Command Block.
Then:
A. The CPU initializes all the appropriate registers and
Command Blocks, and issues a Start Enable by
writing a “1” to Register 0, bit 0.
G. Since this is a BC-RT transfer, the BCRT transmits the
receive command followed by two data words from
locations 0404H - 0405H in memory. The BCRT reads
the second data word from memory while transmitting
the first.
B. The BCRT, through executing a DMA cycle, reads the
control word, command words, and the Data List
Pointer. The delay timer starts and message
execution begins by transmitting the receive and
transmit commands stored in the Command Blocks.
The BCRT then waits to receive the status word back
from the transmitting RT.
H. The BCRT receives the status response from the RT.
In this case, the status word indicates, by the ME bit
being low, that the message is valid. The status word
also has the Subsystem Fail bit set.
I. The status word is stored in the Command Block.
The BCRT, having encountered the end of the list,
halts message transactions and waits for another
start signal.
C. The BCRT receives the RT status word with all status
bits low from the transmitting RT and stores the
status word in Command Block 1. The incoming data
words from the transmitting RT follow. The BCRT
stores them in memory locations 0400H - 0403H.
J. The BCRT asserts a High-Priority Interrupt indicating
the end of the command list. Due to the polling
comparison match, the BCRT also asserts a Standard
Priority Interrupt and logs the event in the Interrupt
Log List.
If the status word indicates that the message cannot
be transmitted (Message Error), the response timeout clock counts to zero and the allotted message
time runs out. An auto-retry can be initiated if
programmed to do so. Nevertheless, the ME bit in the
control word is set.
36-00-09-000
Revision 1.0.0
32
Cobham Semiconductor Solutions
Cobham.com/HiRel
8.0 EXCEPTION HANDLING AND INTERRUPT LOGGING
The exception handling scheme the BCRT uses is based on
an interrupt structure and provides a high degree of
flexibility in:
The host CPU initializes the list by setting the tail pointers.
This gives flexibility in the list capacity and the ability to link
the list around noncontiguous blocks of memory. The host
CPU sets the list’s starting address using the Interrupt Log
List Register. The BCRT then updates this register with the
address of the next list entry.
• defining the events that cause an interrupt,
• selecting between High-Priority and Standard
interrupts, and
The internal High-Priority Interrupt Status/Reset Register
indicates the cause of a High-Priority Interrupt. The HighPriority Interrupt signal is reset by writing a “1” to the set
bits in this register.
• electing the amount of interrupt history retained.
The interrupt structure consists of internal registers that
enable interrupt generation, control bits in the RT and BC
data structures (see the Remote Terminal Descriptor
Definition section, page 24, and the Bus Controller
Command Block definition, page 27), and an Interrupt Log
List that sequentially stores an interrupt events record in
system memory.
The interrupt structure also uses three BCRT-driven output
signals to indicate when an interrupt event occurs:
STDINTL Standard Interrupt Level. This signal is asserted
when one or moreof the events enabled in the
Standard Interrupt Enable Register occurs. Clear
the signal by resetting the Standard Interrupt
bit in the High-Priority Interrupt Status/Reset
Register.
The BCRT generates the Interrupt Log List (see figure 17)
to allow the host CPU to view the Standard Interrupt
occurrences in chronological order. Each Interrupt Log List
entry contains three words. The first, the Interrupt Status
Word, indicates the type of interrupt (entries are only for
interrupts enabled). In the BC mode, the second word is a
Command Block Pointer that refers to the corresponding
Command Block. In the RT mode, the second word is a
Descriptor Pointer that refers to the corresponding
subaddress descriptor. The CPU-initialized third word, a Tail
Pointer, is read by the BCRT to determine the next Interrupt
Log List address. The list length can be as long or as short
as required. The configuration of the Tail Pointers
determines the list length.
INTERRUPT LOG LIST
POINTER REGISTER
ENTRY #1
STDINTP Standard Interrupt Pulse. This signal is pulsed
for each occurrence of an event enabled in the
Standard Interrupt Enable Register.
HPINT
High-Priority Interrupt. This signal is asserted
for each occurrence of an event enabled in the
High-Priority Interrupt/Enable Register. Writing
to the corresponding bit in the High-Priority
Status/Reset Register
resets it.
INTERRUPT STATUS
WORD
COMMAND BLOCK
POINTER
SUBADDRESS/MODE
CODE DESCRIPTOR
POINTER
TAIL POINTER
ENTRY #2
ENTRY #3
Figure 17. Interupt Log List
36-00-09-000
Revision 1.0.0
33
Cobham Semiconductor Solutions
Cobham.com/HiRel
Interrupt Status Word Definition
All bits in the Interrupt Status Word are active high and have the following functions:
Bit
Number
Description
BIT 15
Interrupt Status Word Accessed. The BCRT always sets this bit during the DMA Write of the Interrupt
Status Word. If the CPU resets this bit after reading the Interrupt Status Word, the bit can help the CPU
determine which entries have been acknowledged.
BIT 14
No Response Time-Out (Message Error condition). Further defines the Message Error condition to indicate
that a Response Time-Out condition has occurred.
BIT 13
(RT) Message Error (ME). Indicates the ME bit was set in the 1553 status word response.
BITs12-8 Reserved.
BIT 7
(RT) Subaddress Event or Mode Code with Data Word Interrupt. Indicates a descriptor control word has
been accessed with either an Interrupt Upon Valid Command Received bit set or an Interrupt when Index=0
bit set (and the Index is decremented to 0).
BIT 6
(RT) Mode Code without Data Word Interrupt. Indicates a mode code has occurred with an Interrupt When
Addressed interrupt enabled.
BIT 5
(RT) Illegal Broadcast Command. Applies to receive commands only. This bit indicates that a received
command,due to an illegal mode code or subaddress field, has been received in the broadcast mode. This
does not include invalid commands.
BIT 4
(RT) Illegal Command. This indicates that an illegal command has occurred due to an illegal mode code or
subaddress and T/R field. This does not include invalid commands.
BIT 3
(BC) Polling Comparison Match. Indicates a polling comparison interrupt.
BIT 2
(BC) Retry Fail. Indicates all the programmed retries have failed.
BIT 1
(BC, RT) Message Error. Indicates a Message Error has occurred.
BIT 0
(BC) Interrupt and Continue. This corresponds to the interrupt and continue function described in the
Command Block.
36-00-09-000
Revision 1.0.0
34
Cobham Semiconductor Solutions
Cobham.com/HiRel
36-00-09-000
Revision 1.0.0
35
BCRTMP
ACTIVITY
DESCRIPTION
READ LOG LIST TAIL PTR
STORE CMD BLOCKPTR
STORE INTERRUPT STATUS WORD
RECOGNIZE ME BIT
STORE STATUS WORD #2
BCRTMP DMA
ACTIVITY
FETCH CONTROL WORD
RTI 2
DATA 4
RTI 2
DATA 3
RTI 2
DATA 2
RTI 2
DATA 1
RTI 2
RTI 1
344 to
392μs
400μs
* STATUS
Notes :
1. Times for DMA Arbitration and BCRTMP DMA Activities are not shown to
scale relative to the 1553B message word lengths. This is done to
illustrate the operation of these signals.
2. * = response time of 4 to 12ms.
3. DMA Arbitration represents the DMAR¯ to DMACK- sequence.
4. The scenario assumes that all DMA grants (DMAG) are received in the
required period of time.
5. These times depend on the DMAG response time.
FETCH DATA POINTER
FETCH COMMAND WORD #1
INTERRUPT
FETCH DATA POINTER
FETCH COMMAND WORD #1
FETCH CONTROL WORD
START BCRTMP
INITIALIZE REGISTERS
STATUS
RTI
BC
AUTO RETRY
CMD #1 CMD #2 * STATUS
BC
FETCH COMMAND WORD #2
BCRTMP DMA
ARBITRATION3
FETCH COMMAND WORD #2
MANCHESTER
DATA BUS B
*
STORE STATUS WORD #1
DATA 2
BC
STORE DATA WORD#1
484 to
492μs
STORE DATA WORD #2
DATA1
BC
RTI 1
* STATUS
DATA 4
RTI 2
STORE DATA WORD#3
DATA 3
RTI 2
STORE DATA WORD#4
DATA 2
RTI 2
STORE STATUS WORD #1
CMD
RTI 2
STATUS DATA1
RTI 2
STORE DATA WORD#1
BC
*
175 to
199μs
STORE DATA WORD#2
400μs
BC
CMD #1 CMD #2
BC
168 to
192μs
STORE DATA WORD #3
MANCHESTER
DATA BUS A
BCRTMP
ACTIVITY
DESCRIPTION
BCRTMP DMA
ACTIVITY
INTERRUPT
BCRTMP DMA
ARBITRATION3
MANCHESTER
DATA BUS B
MANCHESTER
DATA BUS A
0μs
TIME OUT TO 400 μS
FETCH TAIL POINTER
STORE STATUS WORD #2
STORE DATA WORD#4
EOL IN CONTROL WORD
SO STOP BCRTMP
STORE INTERRUPT STATUS WORD
FETCH DATA WORD #2
FETCH DATA WORD#1
FETCH DATA POINTER
FETCH COMMAND WORD
FETCH CONTROL WORD
TIME OUT TO 400 ms
Figure 18. Bus Controller Scenario
Cobham Semiconductor Solutions
Cobham.com/HiRel
BIT TIMES
1
2
3
4
5
6
7
5
COMMAND WORD
SYNC
REMOTE TERMINAL
ADDRESS
8
9
10
11
1
12
13
14
15
16
5
SUBADDRESS/
MODE
T/R
17
18
19
5
20
1
DATA WORD
COUNT/MODE CODE
P
DATA WORD
SYNC
DATA
P
Figure 19. MIL-STD-1553B Word Formats
PARITY
TERMINAL FLAG
SUBSYSTEM FLAG
DYNAMIC BUS CONTROL ACCEPTANCE
BUSY
RESERVED
BROADCAST COMMANDRECEIVED
Note:
T/R = transmit/receive
P = parity
SERVICE REQUEST
REMOTE TERMINAL
ADDRESS
INSTRUMENTATION
SYNC
MESSAGE ERROR
STATUS WORD
9.0 ABSOLUTE MAXIMUM RATINGS *
(Referenced to VSS)
SYMBOL
PARAMETER
LIMITS
UNIT
VDD
DC supply voltage
-0.3 to +7.0
V
VI/O
Voltage on any pin
-0.3 to VDD +0.3
V
II
DC input current
TSTG
Storage temperature
TJMAX
Maximum junction temperature
mA
±10
-65 to + 150
Average power dissipation
ΘJC
Thermal resistance, junction to-case
°C
+175
1
PD
°C
300
mW
10
° C/W
Notes:
1. Does not reflect the added PD due to an output short-circuited.
* Stresses outside the listedabsolute maximum ratings may cause permanent damage to the device. This is a stress rating only, and functional
operation of the device at these or any other conditions beyond limits indicated in the operational sections of this specification is not recommended.
Exposure to absolute maximum rating conditions for extended periods may affect device reliability.
RECOMMENDED OPERATION CONDITONS
(Referenced to VSS)
SYMBOL
PARAMETER
LIMITS
UNIT
.
VDD
DC supply voltage
4.5 to 5.5
V
TC
Temperature range
-55 to +125
°C
FO
Operating frequency
12 ±.01%
36-00-09-000
Revision 1.0.0
36
MHz
Cobham Semiconductor Solutions
Cobham.com/HiRel
10.0 DC ELECTRICAL CHARACTERISTICS
(VDD = 5.0V + 10%; -55°C <TC <+125°C)
SYMBOL
PARAMETER
CONDITION
MINIMUM
VIL
Low-level input voltage
TTL inputs
VIH
High-level input voltage
TTL inputs
IIN
Input leakage current
TTL inputs
Inputs w/ pull-up resistors
Inputs w/ pull-up resistors
VIN = VDD or VSS
VIN = VDD
VIN = VSS
VOL
Low-level output voltage
TTL outputs
IOL = 3.2mA
VOH
High-level output voltage
TTL outputs
IOH = -400mA
2.4
IOZ
Three-state output leakage
current
TTL outputs
VOUT = VDD or VSS
-10
IOS
Short-circuit output current
VDD = 5.5V, VOUT = VDD
VDD = 5.5V, VOUT = 0V
-100
CIN
Input capacitance
COUT
CIO
IDD
QIDD
0.8
2.2
3
Bidirect I/O capacitance
3
Average operating current
Quiescent current
1, 2
3
Output capacitance
MAXIMUM
1, 4
-1
-1
-900
UNIT
V
V
-1
-1
-150
μA
μA
μA
0.4
V
V
10
μA
100
mA
mA
ƒ = 1MHz @ 0V
15
pF
ƒ = 1MHz @ 0V
20
pF
ƒ = 1MHz @ 0V
25
pF
ƒ = 12MHz, CL = 50pF
50
mA
3
mA
5
NOTES:
1. Supplied as a design limit. Tested only at initial qualification and after any design or proess changes which may affect this parameter.
2. Not more than one output may be shorted at a time for a maximum duration of one second.
3. Measured only for initial qualification, and after process or design changes which may affect input/output capacitance.
4. Includes current through input pull-up. Instantaneous surge currents on the order of 1 ampere can occur during output switching.
Voltage supply should be adequately sized and decoupled to handle a large current surge.
5. All inputs with internal pull-ups should be left floating. All other inputs should be tied high or low.
36-00-09-000
Revision 1.0.0
37
Cobham Semiconductor Solutions
Cobham.com/HiRel
11.0 AC ELECTRICAL CHARACTERISTICS
(OVER RECOMMENDED OPERATING CONDITIONS)
VIH MIN
INPUT VIL MAX
ta
IN-PHASE
OUTPUT
OUT-OF-PHASE
OUTPUT
VIH MIN
VIL MAX
1
1
tc
2
tb
2
2
td
2
VOH MIN
VOL MAX
VOH MIN
VOL MAX
te
VOH MIN
BUS
VOL MAX
tf
tg
th
SYMBOL
ta
tb
PARAMETER
INPUT↑
INPUT↑
INPUT↑
INPUT↓
INPUT↓
INPUT↓
INPUT↑
INPUT↑
tc
td
te
tf
tg
to response↑
to response↓
to response↓
to response↑
to data valid
to high Z
to high Z
to data valid
th
Notes:
1. Timing measurements made at (VIH MIN + VIL MAX)/2.
2. Timing measurements made at (VOL MAX + VOH MIN)/2.
3. Based on 50pF load.
4. Unless otherwise noted, all AC electrical characteristics are guaranteed by design or characterization.
Figure 20. Typical Timing Measurements
5V
IREF (source)
90%
Device under
Test
50pF
3V
90%
VREF
•
10%
10%
0V
< 2ns
IREF (sink)
< 2ns
Input Pulses
Output Loading
Note:
50pF including scope probe and test socket
Figure 21. AC Test Loads and Input Waveforms
36-00-09-000
Revision 1.0.0
38
Cobham Semiconductor Solutions
Cobham.com/HiRel
DMA GRANT RECOGNIZED ON THIS EDGE
MCLKD2
tSHL1
DMAR
DMAG
tPW2
DMACK
TSCTL
MEMCSO
ADDRESS
DATA
RWR/RRD
(2)
AEN
BURST
tPHL1
tOOZL1
tPZL1
tPHL2
tPHL4
SYMBOL
tSHL16
tPHL1
tPHL21
tPZL16
tHLH2
tPHL3
tPW21
tOOZL1
tPHL4
tPHL4
PARAMETER
DMACK↓ to DMAR High Impedance
DMAG↓ to DMACK↓ 3
DMAG↓ to TSCTL↓
TSCTL↓ to ADDRESS valid
RWR/RRD↑ to DMACK↑
TSCTL↓ to RWR/RRD↓
DMAG↓ to DMAG↑
DMAR↓ to BURST↑
DMAR↓ to DMAG↓ 5
DMAR↓ to DMAG↓ 4
tPHL3
MIN
-12
0
2xMCLK
-15
THMC1-15
MCLK-20
MCLK
-10
0
0
tHLH2
MAX
10
45
4xMCLK
40
THMC1+20
MCLK+20
6xMCLK
10
3.5 (1.9)
1.9 (0.8)
UNITS
ns
ns
ns
ns
ns
ns
ns
ns
μs
μs
Notes:
1. Guaranteed by functional testing.
2. See figures 23 & 24 for detailed DMA read and write timing.
3. DMAG must be asserted at least 45ns prior to the rising edge of MCLKD2 in order to be recognized for the next MCLKD2 cycle.
If DMAG is not asserted at least 45ns prior to the rising edge of MCLKD2, DMAG is not recognized until the following MCLKD2 cycle.
4. Provided MCLK = 12MHz. Number in parentheses indicates the longest DMAR¯ to DMAG¯ allowed during worst-case bus switching
conditions in order to meet MIL-STD-1553B RT Response Time. The number not in parentheses applies to all other circumstances.
5. Provided MCLK = 6MHz. Number in parentheses indicates the longest DMAR¯ DMAG¯ allowed during worst-case bus switching
conditions in order to meet MIL-STD-1553B RT Response Time. The number not in parentheses applies to all other circumstances
6. Tested only at initial qualification, and after any design or process changes which may affect this characteristic.
MCLK = period of the memory clock cycle.
BURST signal is for multiple-word DMA accesses.
THMC1 is equivalent to the positive phase of MCLK (see figure 23).
Figure 22. BURST DMA Timing
36-00-09-000
Revision 1.0.0
39
Cobham Semiconductor Solutions
Cobham.com/HiRel
tPLH1
tIOHL1
THMC1
THMC2
MCLK
MCLKD2
TSCTL
MEMCSO
tPLH2
tHLZ2
ADDRESS
DATA
RRD
tSHL1
SYMBOL
tSLH1
tPW1
PARAMETER
tHLZ1
MIN
tSHL1
ADDRESS valid to RRD↓
tPW1
RRD↓ to RRD↑
tHLZ2
RRD↑ to ADDRESS High Impedance (ADDRESS hold)
tHLZ1
RRD↑ to DATA High Impedance
tSLH1
DATA valid to RRD↑
tPLH1 1
MCLK↑ to MCLKD2↑
tPLH2
tIOHL1 1
(ADDRESS setup) THMC2-10
MAX
UNITS
THMC2+10
ns
MCLK-10
MCLK+5
ns
THMC1-15
THMC1+20
ns
(DATA hold)
5
-
ns
(DATA setup)
40
-
ns
0
40
ns
MCLK↑ to TSCTL/MEMCSO↓
0
40
ns
MCLK↑ to RRD↓
0
60
ns
Note:
1. Guaranteed by test.
Figure 23. BCRT DMA Read Timing (One-Word Read)
36-00-09-000
Revision 1.0.0
40
Cobham Semiconductor Solutions
Cobham.com/HiRel
tPLH1
tIOHL1
THMC1
THMC2
MCLK
MCLKD2
TSCTL
MEMCSO
tPLH2
tHLZ2
ADDRESS
DATA
RWR
tSLH1
tSHL1
tHLZ1
tPW1
SYMBOL
tSHL1
tOOZL1 1
tHLZ1
tHLZ2
tPW1
tPLH1 1
tPLH2
tIOHL1 1
PARAMETER
MIN
MAX
ADDRESS valid to RWR↓
(ADDRESS setup) THMC2-10 THMC2+15
RWR↓ to DATA valid
30
-5
RWR↑ to DATA High Impedance
(DATA hold)
THMC1-15 THMC1+20
RWR↑ to ADDRESS High Impedance (ADDRESS hold) THMC1-15 THMC1+20
RWR↓ to RWR↑
MCLK-10 MCLK+5
MCLK↑ to MCLKD2↑
0
40
MCLK↑ to TSCTL/MEMCSO↓
0
40
MCLK↑ to RWR↓
0
60
Note:
1. Guaranteed by test.
UNITS
ns
ns
ns
ns
ns
ns
ns
ns
Figure 24. BCRT DMA Write Timing (One-Word Write)
36-00-09-000
Revision 1.0.0
41
Cobham Semiconductor Solutions
Cobham.com/HiRel
tOOZH2
tOOZH1
tHLH1
ADDRESS
DATA
RD+CS
tHLH2
tPW1
SYMBOL
tOOZH2
tHLH2
tOOZH1 2
tHLH1
tPW1
tPW21
tPW2
PARAMETER
ADDRESS valid to DATA valid
RD+CS↑ to DATA High Impedance
RD+CS↓ to DATA valid
RD+CS↑ to ADDRESS High Impedance
RD+CS↓ to RD+CS↑
RD+CS↑ to RD+CS↓
(DATA hold)
(DATA access)
(ADDRESS hold)
MIN
0
5
60
80
MAX
80
50
60
-
UNITS
ns
ns
ns
ns
ns
ns
Notes:
1. Guaranteed by functional test.
2. User must adhere to both tOOZH1 and tOOZH2 timing constraints to ensure valid data.
Figure 25. BCRT Register Read Timing
tSHL1
tPW1
tHLH2
ADDRESS
DATA
WR+CS
tHLH1
tPW2
tSHL2
SYMBOL
tSHL1
tSHL2
tPW1
tHLH1
tHLH2
tPW2
PARAMETER
ADDRESS valid to WR+CS↓
DATA valid to WR+CS↓
WR+CSØ to WR+CS↑
WR+CS↑ to DATA High Impedance
WR+CS↑ to ADDRESS High Impedance
WR+CS↑ to WR+CS↓
Notes:
1. Guaranteed by functional test.
MIN
(ADDRESS setup)
(DATA setup)
(DATA hold)
(ADDRESS hold)
60
5
60
10
10
80
MAX
-
UNITS
ns
ns
ns
ns
ns
ns
Figure 26. BCRT Register Write Timing
36-00-09-000
Revision 1.0.0
42
Cobham Semiconductor Solutions
Cobham.com/HiRel
tPHL1
RD
RRD
tPHL2
WR
RWR
tPHL3
MEMCSI
MEMCSO
SYMBOL
tPHL1 1
tPHL2 1
tPHL3 1
PARAMETER
RD↓ to RRD↓
WR↓ to RWR↓
MEMCSI↓ to MEMCSO↓
MIN
MAX
0
0
30
30
0
30
UNITS
ns
ns
ns
Figure 27. BCRT Dual-Port Interface Timing Delays
tPZL1
MANCHESTER C
D
D
DMA
ACTIVITY
SYMBOL
tPZL11, 2
PARAMETER
MIN
Data word to DMA activity
0
MAX
UNITS
μs
4
This diagram indicates the relationship between the incoming Manchester code DMA activity (i.e., DMAR↓ to DMACK↑ ).
Note:
1. The pulsewidth = (11μs -tDMA -tPZL1) where tDMA is the time to complete DMA activity (i.e., DMAR↓ to DMACK↑ ).
2. Guaranteed by functional test.
Figure 28. DMA Activity (RT Mode)
36-00-09-000
Revision 1.0.0
43
Cobham Semiconductor Solutions
Cobham.com/HiRel
tPLH2
MCLK
MCLKD2
DMAR
DMAG
DMAGO
DMACK
tSHL1
tPLH1
SYMBOL
MIN
MAX
UNITS
DMAG↓ to DMAGO↓
0
30
ns
tSHL1
DMACK↓ to DMAR High Impedance
-12
10
ns
tPLH2
MCLK↑ to MCLKD2↑
0
40
ns
tPLH11
PARAMETER
Notes:
1. When DMAG is asserted before DMAR, the DMAG signal passes through the BCRT as DMAGO.
Figure 29. BCRT Arbitration when DMAG is Asserted before Arbitration
36-00-09-000
Revision 1.0.0
44
Cobham Semiconductor Solutions
Cobham.com/HiRel
DMAR
DMAG
DMACK
RWR
RRD
TSCTL
BURST
STDINTL
STDINTP
tOOHL1
tOOLH1
tOOHL2
tPW1
SYMBOL
tOOLH1
PARAMETER
TSCTL↑ to STDINTP/STDINTL↓
MIN
MAX
-
1
μs
tPW1
STDINTP↓ to STDINTP↑
310
340
ns
tOOHL1
DMACK↓ to RWR↓
tOOHL2
DMAG↓ to STDINTL↓
3xMCLK-10
8xMCLK
UNITS
5xMCLK
12xMCLK
ns
μs
Note:
Address and data bus relationships (not shown) are identical to figure 22.
Figure 30. BCRT Interrupt Log List Entry Operation Timing
36-00-09-000
Revision 1.0.0
45
Cobham Semiconductor Solutions
Cobham.com/HiRel
BCRTSEL
MRST
D0
D1
D2
D3
D4
D5
D6
D7
VSS
VDD
D8
D9
D10
D11
D12
D13
D14
D15
BCRTF
12.0 PACKAGE OUTLINE DRAWINGS
TIMERON
11 10
9
8
7
6
5
4
3
2
1
84 83 82 81 80 79 78 77 76 75
LOCK
TAZ
TAO
RAZ
RAO
TBZ
TBO
RBZ
RBO
CLK
VSS
VDD
EXTOVR
TIMERON
CHA/B
COMSTR
12
74
13
73
14
72
15
71
16
70
17
69
18
68
19
67
20
66
21
65
22
64
23
63
24
62
25
61
26
60
27
59
RTA0
RTA1
RTA2
RTA3
RTA4
28
58
29
57
30
56
31
55
32
54
BURST
TEST
SSYSF
MCLKD2
HPINT
STDINTP
STDINTL
DMAGO
AEN
MCLK
VDD
VSS
CS
RD
WR
MEMCSI
DMACK
DMAG
DMAR
TSCTL
MEMCSO
RTPTY
A0
A1
A2
A3
A4
A5
A6
A7
VSS
VDD
A8
A9
A10
A11
A12
A13
A14
A15
RWR
RRD
33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53
Figure 31a. BCRT Flatpack Pin Identification (Top View)
(Flatpack Leads Omitted for Clarity)
36-00-09-000
Revision 1.0.0
46
Cobham Semiconductor Solutions
Cobham.com/HiRel
L
BCRTSEL
TAO
RAZ
TBZ
RBO
VDD
DD
EXTOVR
COMSTR
RTA1
RTA2
RTA4
K
D0
LOCK
TAZ
RAO
RBZ
TBO
TIMERON
RTAO
RTA3
RTPTY
A1
J
D1
MRST
CLK
VSS
A0
A2
H
D3
D2
A3
A4
G
D6
D5
D4
A5
A6
A7
F
D7
D10
V
VSS
VDD
VSS
A11
E
D8
D8
D9
VDD
A8
A10
A9
D
D11
D12
A13
A12
C
D13
D15
RWR
A14
B
D14
BCRTF
TEST
HPINT
A
BURST
BURST
SSYSF
SSYSF
MCLKD2
STDINTP
1
2
3
MCLK
4
DMAGO
VDD
DD
V
VSS
SS
CHA/B
WR
RD
DMACK
TSCTL
MEMCSO
A15
DMAR
RRD
AEN
STDINTL
CS
MEMCSI
DMAG
5
6
7
8
9
10
11
INDEX
CORNER
Figure 31b. BCRT Pingrid Array Pin Indentification (Bottom View)
36-00-09-000
Revision 1.0.0
47
Cobham Semiconductor Solutions
Cobham.com/HiRel
Figure 32a. 84-Lead Flatpack
36-00-09-000
Revision 1.0.0
48
Cobham Semiconductor Solutions
Cobham.com/HiRel
Figure 32b. 84-Lead PGA
36-00-09-000
Revision 1.0.0
49
Cobham Semiconductor Solutions
Cobham.com/HiRel
13.0 ORDERING INFORMATION
UT1553B/BCRT Version B Bus Controller/Remote Terminal
*
B
- * *
*
Lead Finish: (Notes: 1 and 2)
(A) = Solder
(C) = Gold
(X) = Optional
Screening Level: (Notes: 3 and 4)
(C) = HiRel Flow (Temperature range -55oC to +125oC)
(P) = Prototype Flow (Temperature range 25oC only)
Package Type:
(G) = 84-pin PGA
(W) = 84-pin FP
Device Version:
(B) = Version B
Generic part number:
UT1553B/BCRT
Notes:
1. Lead finish is "C" (Gold) only.
2. If an "X" is specified when ordering, part marking will match the lead finish and will be either "A" (solder) or "C" (gold).
3. HiRel flow per Aeroflex Manufacturing Flows Document.
4. Prototype Flow per Aeroflex Manufacturing Flows Document. Lead finish is GOLD only.
5962 * ******* * * *
Lead Finish:
(A) = Solder
(C) = Gold
(X) = Optional
Case Outline:
(X) = 84-pin PGA
(Y) = 84-pin FP
Class Designator:
(Q) = QML Class Q
Drawing Number: 8862802
Total Dose:
(-) = None
Federal Stock Class Designator: No options
Notes:
1. Lead finish is "C" (Gold) only.
2. If an "X" is specified when ordering, part marking will match the lead finish and will be either "A" (solder) or "C" (gold).
36-00-09-000
Revision 1.0.0
50
Cobham Semiconductor Solutions
Cobham.com/HiRel
REVISION HISTORY
Date
05/27/2016
Rev. #
1.0.0
Change Description
Released Datasheet
Initials
TM
Template Revision: A
36-00-09-000
Revision 1.0.0
51
Cobham Semiconductor Solutions
Cobham.com/HiRel
Cobham Semiconductor Solutions – Datasheet Definitions
Advanced Datasheet - Product In Development
Preliminary Datasheet - Shipping Prototype
Released Datasheet - Shipping QML & Reduced Hi – Rel
For Product Concept/Brief: Export classification information will be added at a later date.
(Search for ECCN (Classification) by part number or SMD HERE. Please pick one of the following
statements. Delete the other statements and this note. Contact your export control officer with questions.)
The product or data that is the subject of this transaction, to be provided by Aeroflex, is subject to the International Traffic
in Arms Regulations (“ITAR”) (22 CFR 120-130) and may not be exported, reexported or otherwise transferred to a foreign
person, or outside the United States without authorization from the U.S. Department of State. By accepting this product or
data, the recipient acknowledges and accepts these controls and agrees to comply with all applicable U.S. laws and
regulations, including the ITAR, in handling this product or data, including any export, reexport or transfer of the product
or data to another person or entity.
The following United States (U.S.) Department of Commerce statement shall be applicable if these commodities, technology,
or software are exported from the U.S.: These commodities, technology, or software were exported from the United States
in accordance with the Export Administration Regulations. Diversion contrary to U.S. law is prohibited.
Cobham Semiconductor Solutions
4350 Centennial Blvd
Colorado Springs, CO 80907
E: [email protected]
T: 800 645 8862
Aeroflex Colorado Springs Inc., dba Cobham Semiconductor Solutions, reserves the right to make changes to any products
and services described herein at any time without notice. Consult Aeroflex or an authorized sales representative to verify
that the information in this data sheet is current before using this product. Aeroflex does not assume any responsibility
or liability arising out of the application or use of any product or service described herein, except as expressly agreed to
in writing by Aeroflex; nor does the purchase, lease, or use of a product or service from Aeroflex convey a license under
any patent rights, copyrights, trademark rights, or any other of the intellectual rights of Aeroflex or of third parties.
36-00-09-000
Revision 1.0.0
52
Cobham Semiconductor Solutions
Cobham.com/HiRel