UT1553 BCRT - Aeroflex Microelectronic Solutions

UT1553B BCRT
p Register-oriented architecture to enhance
FEATURES
p Comprehensive MIL-STD-1553B dual-redundant
programmability
p DMA memory interface with 64K addressability
p Internal self-test
p Remote terminal operations in ASD/ENASD-certified
Bus Controller (BC) and Remote Terminal
(RT) functions
p MIL-STD-1773 compatible
p Multiple message processing capability in BC and
(SEAFAC)
RT modes
p Time-tagging and message logging in RT mode
p Automatic polling and intermessage delay in
BC mode
p Programmable interrupt scheme and internally
generated interrupt history list
p The UT1553B BCRT is not available radiation-harden
ed
p Packaged in 84-pin pingrid array, 84- and 132-lead
flatpack, 84-lead leadless chip carrier packages
p Standard Microcircuit Drawing 5962-88628 available
- QML Q and V compliant
REGISTERS
HIGH-PRIORITY
STD PRIORITY LEVEL
STD PRIORITY PULSE
MASTER
RESET
12MHZ
1553
DATA
CHANNEL
B
TIMERON
DUAL
CHANNEL
ENCODER/
DECODER
MODULE
TIMEOUT
STATUS
CURRENT BC BLOCK/
RT DESCRIPTOR SPACE
INTERRUPT
HANDLER
CLOCK &
RESET
LOGIC
1553
DATA
CHANNEL
A
CONTROL
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
DMA/CPU
CONTROL
16
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
BCRT-1
Table of Contents
1.0
INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1
1.2
2.0
PIN IDENTIFICATION AND DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
3.0
INTERNAL REGISTERS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
4.0
SYSTEM OVERVIEW . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
5.0
SYSTEM INTERFACE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
5.1
5.2
5.3
5.4
5.5
6.0
6.2
6.3
7.0
DMA Transfers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
Hardware Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
CPU Interconnection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
RAM Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20
Transmitter/Receiver Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20
REMOTE TERMINAL ARCHITECTURE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
6.1
RT Functional Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
6.1.1 RT Subaddress Descriptor Definitions . . . . . . . . . . . . . . . . . . . . . . . . . .22
6.1.2 Message Status Word. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24
6.1.3 Mode Code Descriptor Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25
RT Error Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27
RT Operational Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27
BUS CONTROLLER ARCHITECTURE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
7.1
7.2
7.3
7.4
7.5
BCRT-2
Features - Remote Terminal (RT) Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
Features - Bus Controller (BC) Mode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
BC Functional Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29
Polling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31
BC Error Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31
BC Operational Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31
BC Operational Example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33
8.0
EXCEPTION HANDLING AND INTERRUPT LOGGING . . . . . . . . . . . . . . . . . . . . . . . . 34
9.0
MAXIMUM AND RECOMMENDED OPERATING CONDITIONS . . . . . . . . . . . . . . . . 37
10.0
DC ELECTRICAL CHARACTERISTICS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
11.0
AC ELECTRICAL CHARACTERISTICS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
12.0
PACKAGE OUTLINE DRAWINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
1.0 INTRODUCTION
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 UT1553B BCRT is an intelligent, versatile, and easy to
implement device -- a powerful asset to system designers.
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.
Programmable Interrupt Selection
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
host-specified time before executing the next message
in sequence.
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.
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
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 Data Storage
The BCRT stores/retrieves, by subaddress, all messages in
the order in which they are transacted.
Sequential Message Status Information
The BCRT provides message validity, time-tag, and wordcount information, and stores it sequentially in a separate,
cross-referenced list.
Variable Space Allocation
The BCRT uses as little or as much memory (up to 64K)
as needed.
Selectable Data Storage
Address programmability within the BCRT provides
flexible data placement and convenient access.
Illegalizing Mode Codes and Subaddresses
The host can declare mode codes and subaddresses illegal
by setting the appropriate bit(s) in memory.
BCRT-3
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
61
60
62
66
11
12
10
24
53
52
59
54
RD
WR
CS
AEN
BCRTSEL
LOCK
CONTROL
MRST
SIGNALS
EXTOVR
RRD
RWR
MEMCSI
MEMCSO
**
+
++
*
Pin internally pulled up.
Pin at high impedance when not asseted
Bidirectional pin.
Formerly MEMWIN.
(B7)
(C7)
(A7)
(A5)
(L1) * *
(K2) * *
(J2)
(L7) * *
(A11)
(C10)
(A8) * *
(B10)
(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
BCRT-4
BIPHASE OUT
TAZ
TAO
TBZ
TBO
3
4
10
11
BIPHASE IN
RAZ
RAO
RBZ
RBO
7
9
13
15
TERMINAL
ADDRESS* *
RTA0
RTA1
RTA2
RTA3
RTA4
RTPTY
27
29
30
31
32
35
STATUS
SIGNALS
STDINT
STDPUL
HPINT
TIMERON
COMSTR
SSYSF
BCRTF
CHA/B
TEST
DMA
SIGNALS
DMAR
DMAG
DMAGO
DMACK
BURST
TSCTL
70
72
88
74
98
69
79
77
81
86
131
2
130
20
65
64
75
68
RD
WR
CS
AEN
BCRTSEL
LOCK
CONTROL
MRST
SIGNALS
EXTOVR
RRD
RWR
MEMCSI
MEMCSO
**
+
++
*
89
90
92
22
27
95
101
24
97 *
Pin internally pulled up.
Pin at high impedance when not asseted
Bidirectional pin.
Formerly MEMWIN.
36
37
40
41
42
45
47
51
52
54
56
57
58
60
61
63
A0 ++
A1 ++
A2 ++
A3 ++
A4
A5
A6
A7
A8
A9
A10
A11
A12
A13
A14
A15
129
127
125
124
122
120
119
118
114
112
110
108
107
105
103
102
D0
D1
D2
D3
D4
D5
D6
D7
D8
D9
D10
D11
D12
D13
D14
D15
VDD
VDD
VDD
VDD
VDD
VDD
VDD
VDD
17
34
50
66
83
100
115
132
ADDRESS+
LINES
DATA
++
LINES
POWER
1
16
33
49
67
82
99
116
VSS
VSS
VSS
VSS
VSS
VSS
VSS
VSS
GROUND
18
85
94
CLK
MCLK
MCKD2
CLOCK
SIGNALS
( ) Pingrid arraylead identification in parentheses.
LCC, flatpack pin number not in parentheses.
Figure 2b. BCRT 132-lead Functional Pin Description
BCRT-5
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.
2. Flatpack pin numbers are same as LCC.
ADDRESS BUS
NAME
ACTIVE
DESCRIPTION
AO
PIN NUMBER
PGA
J10
TYPE
LCC/FP
34
132 FP
36
TTB
--
Bit 0 (LSB) of the Address Bus
A1
35
K11
37
TTB
--
Bit 1 of the Address Bus
A2
36
J11
40
TTB
--
Bit 2 of the Address Bus
A3
37
H10
41
TTB
--
Bit 3 of the Address Bus
A4
38
H11
42
TTO
--
Bit 4 of the Address Bus
A5
39
G9
45
TTO
--
Bit 5 of the Address Bus
A6
40
G10
47
TTO
--
Bit 6 of the Address Bus
A7
41
G11
51
TTO
--
Bit 7 of the Address Bus
A8
44
E9
52
TTO
--
Bit 8 of the Address Bus
A9
45
E11
54
TTO
--
Bit 9 of the Address Bus
A10
46
E10
56
TTO
--
Bit 10 of the Address Bus
A11
47
F11
57
TTO
--
Bit 11 of the Address Bus
A12
48
D11
58
TTO
--
Bit 12 of the Address Bus
A13
49
D10
60
TTO
--
Bit 13 of the Address Bus
A14
50
C11
61
TTO
--
Bit 14 of the Address Bus
A15
51
B11
63
TTO
--
Bit 15 (MSB) of the Address Bus
BCRT-6
DATA BUS
NAME
DO
D1
D2
D3
D4
D5
D6
D7
D8
D9
D10
D11
D12
D13
D14
D15
LCC/FP
9
8
7
6
5
4
3
2
83
82
81
80
79
78
77
76
PIN NUMBER
PGA
KA
J1
H2
H1
G3
G2
G1
F1
E1
E2
F2
D1
D2
C1
B1
C2
132 FP
129
127
125
124
122
120
119
118
114
112
110
108
107
105
103
102
TYPE
ACTIVE
TTB
TTB
TTB
TTB
TTB
TTB
TTB
TTB
TTB
TTB
TTB
TTB
TTB
TTB
TTB
TTB
-----------------
DESCRIPTION
Bit 0 (LSB) of the Data Bus
Bit 1 of the Data Bus
Bit 2 of the Data Bus
Bit 3 of the Data Bus
Bit 4 of the Data Bus
Bit 5 of the Data Bus
Bit 6 of the Data Bus
Bit 7 of the Data Bus
Bit 8 of the Data Bus
Bit 9 of the Data Bus
Bit 10 of the Data Bus
Bit 11 of the Data Bus
Bit 12 of the Data Bus
Bit 13 of the Data Bus
Bit 14 of the Data Bus
Bit 15 (msb) of the Data Bus
TERMINAL ADDRESS INPUTS
NAME
ACTIVE
DESCRIPTION
RTA0
PIN NUMBER
PGA
K8
TYPE
LCC/FP
28
132 FP
27
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
29
TUI
--
RTA2
30
L10
30
TUI
--
RTA3
31
K9
31
TUI
--
RTA4
32
L11
32
TUI
--
RTA5
33
K10
35
TUI
--
Remote Terminal Address Bit
1. This is bit 1 of the Remote
Terminal Address.
Remote Terminal Address Bit
2. This is bit 2 of the Remote
Terminal Address.
Remote Terminal Address Bit
3. This is bit 3 of the Remote
Terminal Address.
Remote Terminal Address Bit
4. This is bit 4 (MSB) of the
Remote Terminal Address.
Remote Terminal (Address)
Parity. This is oddof the
Remote Terminal Address.
BCRT-7
CONTROL SIGNALS
NAME
ACTIVE
DESCRIPTION
RD
PIN NUMBER
PGA
B7
TYPE
LCC/FP
61
132 FP
79
TI
AL
WR
60
C7
77
TI
AL
CS
62
A7
81
TI
AL
AEN
66
A5
86
TI
AH
BCRTSEL
11
L1
131
TUI
--
Read. The host uses this in conjunction
with CS to read an internal BCRT register.
Write. The host uses this in conjunction
with CS to write an internal BCRT
register.
Chip Select. This selects theBCRT when
accessing the BCRT’s internal register.
Address Enable. The hostCPU uses AEN
to indicate to the BCRT that the BCRT’s
addresslines can be asserted; this is a
precautionary signal provided to avoid
address bus crash. If not used, it must be
tied high.
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
2
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
20
TUI
AL
External Override. Use this in multiredundant applications. Upon receipt, the
BCRT aborts all current activity.
EXTOVR should be connected to COMSTR output of the adjacent BCRT when
used. This pin is internally pulled high.
MRST
10
32
130
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
68
TO
AL
Memory Chip Select Out. This is the
regenerated MEMCSI inout for external
RAM during the pseudo-dual-port RAM
mode. The BCRT also uses it to select
external memory during memory
accesses.
MEMCSI
59
A8
75
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
65
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 BCRT. It is
also the signal the BCRT uses to read
from memory. It is asserted following
receipt of DMAG. When the BCRT performs multiple reads, this signal is
pulsed.
RWR
52
C10
64
TO
AL
RAM Write. In the pseudo-dual-port
RAM mode, the CPU and BCRT use this
to write to external RAM. This signal is
asserted following receipt of DMAG. For
multiple writes, this signal is pulsed.
BCRT-8
CONTROL SIGNALS con’t
NAME
ACTIVE
DESCRIPTION
STDINTL
PIN NUMBER
PGA
A6
TYPE
LCC/FP
68
132 FP
89
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 HighPriority Interrupt Status/Reset Register
clears the interrupt.
STDINTP
69
A4
90
TO
AL
Standard Interrupt Pulse. STDINTP
pulses when an interrupt
is logged.
HPINT
70
B4
92
TTO
ZL
High-Priority Interrupt. The High Priority Interrupt level is asserted upon occurance of events enabled in the HighPriority Interrupt Enable Register. The
corresponding bit(s) in the High-Priority
Interrupt Status/Reset Register reset
HPINT.
TIMERON
25
K7
22
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
25
TO
AL
(RT) Command Strobe. The BCRT
asserts this signal after receiving a valid
command. The BCRT deactivates it after
servicing the command.
SSYSF
72
A2
96
TI
AH
(RT) Command Strobe. The BCRT
asserts this signal after receiving a valid
command. The BCRT deactivates it after
servicing the command.
BCRTF
75
B2
101
TO
AH
BCRT 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
37
24
TO
--
Channel A/B. This indicates the active or
last active channel.
TEST
73
B3
97
TO
AL
BCRT Fail. This indicates a Built-in-Test
(BIT) failure. In the RT mode, the Terminal Flag bit in 1553 status word is also
set.
BCRT-9
BIPHASE INPUTS
NAME
ACTIVE
RAO
PIN NUMBER
PGA
K4
TYPE
LCC/FP
16
132 FP
9
DESCRIPTION
TI
--
RAZ
15
L3
7
TI
--
RBO
20
L5
15
TI
--
RBZ
19
K5
13
TI
--
ACTIVE
TAO
PIN NUMBER
PGA
L2
TYPE
LCC/FP
14
132 FP
4
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
3
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
11
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
10
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.
Receive Channel A One. This is the
Manchester-encoded true signal input
from Channel A of the bus receiver.
Receive Channel A Zero. This is the
Manchester-encoded complementary signal input from Channel A of the bus
receiver.
Receive Channel B One. This is the
Manchester-encoded true signal input from
Channel B of the bus receiver.
Receive Channel B Zero. This is the
Manchester-encoded complementary signal input from Channel B of the bus
receiver.
BIPHASE OUTPUTS
NAME
DESCRIPTION
BCRT-10
DMA SIGNALS
NAME
LCC/FP
DMAR
56
PIN NUMBER
PGA
A10
TYPE
ACTIVE
132 FP
70
DESCRIPTION
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
72
TI
AL
DMA Grant. This input to the BCRTM
allows the BCRT to access RAM. It is
recognized 45ns before the rising edge of
MCLKD2.
DMAGO
67
B5
88
TO
AL
DMA Grant Out. If DMAG is received but
not needed, it passes through to this output.
DMACK
58
B8
74
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
98
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
69
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
LCC/FP
CLK
21
PIN NUMBER
PGA
35
TYPE
ACTIVE
132 FP
18
DESCRIPTION
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
85
TI
--
Memory Clock. This is the input clock
frequency the BCRT 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
BCRT DMA timing diagrams in this
chapter.
MCLKD2
71
A3
94
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.
TYPE
ACTIVE
DESCRIPTION
PWR
--
+5V
GND
--
Ground
POWER AND GROUND
NAME
PIN NUMBER
LCC/FP
PGA
132 FP
VDD
23, 43, 64, 84 L6, C9, C6, 17, 34, 50, 66,
’E3
83, 100, 115,
132
VSS
1, 22, 42, 63
F3, J6, F10, 1, 16, 33, 49,
67, 82, 99, 116
B6
BCRT-11
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
BITs15-12
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:
•
•
BCRT-12
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.
#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 a ddress
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).
BCRT-13
#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
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.
BCRT-14
#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
(BC) Polling Comparison Match. This enables an interrupt indicating that a polling event has occurred. The user
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.
BCRT-15
#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 changestothe
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.
BCRT-16
#0
BC/RT CONTROL REGISTER
15
14
UNUSED
7
CHNSEL
BUSAEN
#1
4
3
2
1
0
RTYBCME
RTYTO
RTYME
RTYBSY
STEN
13
12
11
DYNBUS
RT FLAG
SRQ
10
BUSY
9
8
BIT
RESET
5
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
D14
D13
12
11
10
D12
D11
D10
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
#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
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
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
Table 1. BCRT Registers
BCRT-17
#9
STANDARD INTERRUPT ENABLE REGISTER
15
14
13
12
UNUSED
#10
#12
#13
UNUSED
UNUSED
7
6
5
4
UNUSED
UNUSED
ILLBCMD
ILLCMD
REMOTE TERMINAL ADDRESS REGISTER
15
14
13
12
INSTR
#11
UNUSED
BUSY2
SS FLAG
DBC
11
10
9
8
UNUSED
UNUSED
UNUSED
UNUSED
3
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
BUILT-IN-TEST START 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
PROGRAMMED 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
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
RAM
CPU MEMORY
CONTROL SIGNALS
RRD
RWR
MEMCSO
BCRT
RD
WR
MEMCSI
Figure 3a. Pseudo DualX0106Port RAM
Control Signals
BCRT-18
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.
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
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.
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.
5.0 SYSTEM INTERFACE
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.
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.
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.
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.
For complete circuit description, such as arbitration logic
and I/O, please refer to the appropriate application note.
5.3 CPU Interconnection
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.
Standard DMA Configuration
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.
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.
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.
Register Access
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
BCRT-19
BUFFERS
16 DATA
RAM
HOST
CPU
16 ADDRESS
CONTROL
CONTROL/ARBITRATION
BCRT
(DUAL REDUNDANT)
TRANSMITTER
TIMEOUT
DUAL
TRANSCEIVER
XFMR
XFMR
BUS A
1553 BUS
BUS B
Figure 3b. CPU/BCRT Interface -- Pseudo-Dual-Port RAM Configuration
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.
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.
ADDRESS BUS
DMAR
DMAG
CPU
DMACK
BCRT
DATA BUS
RRD RWR
SHARED
MEMORY
AREA
OE
•
WE
•
CS
•
Figure 3c. DMA Signals
BCRT-20
MEMCSO
RAM
DATA
ADDRESS
BCRT
MEMORY
BUFFER
CONTROL
CPU
ARBITRATION
DUAL
TRANSCEIVER
XFMR
XFMR
BUS A
1553 BUS
BUS B
Figure 3d. CPU/BCRT Interface -- DMA Configuration
.
6.0 REMOTE TERMINAL
ARCHITECTURE
BCRT
TIMERON
CHANNEL A
CHANNEL A
TXINHA
CHANNEL B CHA/B
CHANNEL B
DUAL
TRANSCEIVER
TXINHB
Figure 4. Dual-Channel Transceiver
The BCRT also provides a TIMERON signal output and an
active channel output indicator (CHA/B) to assist in meeting
the MIL-STD-1553B fail-safe timer requirements (see
figure 4).
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.
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.
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).
BCRT-21
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.
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.
- STARTING ADDRESS
INITIALIZED BY CPU
IN THE RT DESCRIPTOR
SPACE REGISTER
RECEIVE
SUBADDRESS #1
RECEIVE
SUBADDRESS #2
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.
ILLEGAL BROADCAST
SUBADDRESS
ILLEGAL
SUBADDRESS
RECEIVE
INTERRUPT WHEN
ADDRESSED
SUBADDRESS #30
INTERRUPT WHEN
INDEX = 0
UNUSED
UNUSED
15
TRANSMIT
SUBADDRESS #1
TRANSMIT
SUBADDRESS #2
UNUSED
10
9
8
7
I
I
I
I
6
0
INDEX
MESSAGE STATUS LIST POINTER
DATA LIST POINTER
TRANSMIT
SUBADDRESS #30
UNUSED
Figure 6. Remote Terminal Subaddress Descriptor
UNUSED
MODE CODE
#’s 0 & 16
MODE CODE
#’s 1 & 17
MODE CODE
#’s 15 & 31
Figure 5. Descriptor Space
BCRT-22
FOR FUTURE EXPANSION
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
corresponding to the erroneous message.
data
• 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.
BCRT-23
6.1.2 Message Status Word
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).
15
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
#3
#2
#2
#4
MESSAGE STATUS
LIST POINTER
MESSAGE
#3
#5
DATA LIST
POINTER
MESSAGE
#4
(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. Thisbitis
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
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.
BCRT-24
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)
ILLEGALIZE RECEIVE MODE CODE
(WITH DATA WORD)
INTERRUPT ON RECEPTION OF MODE CODE
(WITH DATA WORD)
INTERRUPT IF INDEX = 0
15
14
13
12
11
10
9
8
7
0
6
INDEX
MESSAGE STATUS LIST POINTER
DATA LIST POINTER
RESERVED
Figure 9b. (RT) Mode Code Descriptor
BCRT-25
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 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).
Dynamic Bus Control #00000
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.
Synchronize (Without Data Word) #00001
If enabled in the Mode Code #00001 Descriptor Control
Word, the BCRT asserts an interrupt when this mode code
is received.
Transmit Status Word #00010
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.
BCRT-26
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.
Override Inhibit Terminal Flag Bit #00111
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 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.
Transmit Last Command #10010
The BCRT transmits the last command executed and the
corresponding 1553 status word.
Transmit BIT Word #10011
The BCRT transmits BIT information from the BIT
Register.
Selected Transmitter Shutdown #10100
On receiving this mode code, the BCRT simply stores the
associated data word.
Override Selected Transmitter Shutdown #10101
On receiving this mode code, the BCRT simply stores the
associated data word.
Mode codes 9-15 and 22-31 are reserved for future
expansion of MIL-STD-1553B.
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:
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.
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
Valid Command Received.
COMSTR goes active
•
DMA Descriptor Read. After receiving a valid
command, the BCRT initiates a burst DMA:
DMA arbitration (BURST)
Control Word read
Message Status List Pointer read
Data List Pointer read
Data Transmitted/Received.
•
Data Word DMA.
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)
•
Descriptor Write.
After the BCRT processes the message, a final DMA
burst occurs to update the descriptor block, if
necessary:
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)
Note the following exceptions:
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.
Messages with errors prevent updates to the
Data List Pointer.
If the message index was zero, neither the
Message Status List Pointer nor the Data
List Pointer is updated.
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.
BCRT-27
7.0 B US CONTROLLER ARCHITECTURE
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.
A programmable auto retry function is selectable from the
control word and Control Register.
The auto retry can be activated when any of the following
occurs:
•
Busy bit set in the status word
•
Message Error (indicated by the RT status response)
•
Response Time-Out
•
Message Error detected by the Bus Controller
One to four retries are programmable on the same or
opposite bus.
HEAD POINTER
CONTROL WORD
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 1
COMMAND WORD 2 (RT-RT ONLY)
DATA LIST POINTER
A polling function is also provided. The Bus Controller,
when programmed, compares incoming status words to a
host-specified 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.
STATUS WORD 1
STATUS WORD 2 (RT-RT ONLY)
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
COMMAND BLOCK
DATA LIST POINTER
HP
DATA WORD #1
DATA WORD #2
X
TP
LAST DATA WORD
#3
X IS BETWEEN 1 & 32
HP
Figure 11. Data Placement
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.
TP
#4
HP
TP
Figure 12. Command Block Chaining
BCRT-28
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-by-message
flexibility. In addition, a programmable interrupt scheme,
programmable intermessage timing delays, and internal
registers enhance the BCRT’s operation.
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 Command
Block register with the next Command Block Address. The
BCRT then executes the sequential
15
MESSAGE
ERROR
14
SKIP
13
INTERRUPT
AND
CONTINUE
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 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
BCRT-29
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
Number
Description
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.
BCRT-30
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. Contiguous Data Storage
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 RESPONSE REGISTER
(RT STATUS WORD)
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.
•
Example 1. No bit match is present
PCR
00100100000
RT’s 1553 Status Word response
00000100000
Result
Polling Comparison Interrupt
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.
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
PCR
00000000001
RT’s 1553 Status Word response
00000100010
Result
No Polling Comparison Interrupt
Example 2. Bit match is present
RT
RT
A. For BC-to-RT Command Blocks:
The BCRT transmits the Command Word.
•
Data Word DMA
DMA arbitration
Data Word read (starting at Data List Pointer
address, incremented for each successive
word)
The BCRT transmits the Data Word. Data Word DMAs
and transmissions continue until all Data Words are
transmitted.
•
Status Word DMA
The BCRT receives the RT Status Word.
DMA arbitration
Status Word write (to sixth location of
Command Block)
BCRT-31
B. For RT-to-BC Command Blocks:
The BCRT transmits the Command Word.
•
Status Word DMA
Exception Handling.
If an interrupting condition occurs during the message, the
following occurs:
For High-Priority Interrupts:
The BCRT receives the RT Status Word.
DMA arbitration
Status Word write (to sixth location of
Command Block)
The BCRT receives the first Data Word.
•
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:
Data Word DMA
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
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.
C. For RT(B)-to-RT(A) Command Blocks:
If Retries are enabled and a Retry condition occurs, the
following DMA occurs:
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 1 to RT(B).
•
Command Word 2 DMA
DMA arbitration
Command Word 2 read (from fourth location
of Command Block)
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 (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
DMA arbitration
Status Word write (to sixth location of
Command Block)
The BCRT receives the first Data Word
•
Data Word DMA (only if the BCRT is enabled to
monitor the RT-to-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:
Status Word DMA for RT(B) Status Word
DMA arbitration
Status Word write (to seventh location of
Command Block)
•
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
The BCRT proceeds again from point A, B, or C as
shown above.
BCRT-32
7.5 BC Operational Example (see figure 18 on page 35)
The BCRT is programmed initially to accomplish the
following:
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 onlyone
retry attempt, if the incoming Status Word is received
with the Message Error bit set.
•
Wait for a time delay of 400µs before proceeding to the
next Command Block.
•
The Data List Pointer contains the address 0400H.
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.
E. The timer delay between the two successive
transactions counts down another 135 microseconds
before proceeding. This is determined as follows:
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).
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.
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.
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.
If the status word indicates that the message cannot be
transmitted (Message Error), the response time-out
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.
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 265µs.
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.
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.
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.
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.
BCRT-33
8.0 E XCEPTION 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:
•
defining the events that cause an interrupt,
•
selecting between High-Priority and Standard
interrupts, and
•
selecting the amount of interrupt history retained.
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.
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.
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 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
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.
STDINTP
Standard Interrupt Pulse. This signal ispulsed
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
BCRT-34
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.
BITs 12-8 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.
BCRT-35
BCRT-36
READ LOG LIST TAIL PTR
STORE CMD BLOCKPTR
STORE INTERRUPT STATUS WORD
RECOGNIZE ME BIT
STORE STATUS WORD #2
BCRTMP
ACTIVITY
DESCRIPTION
FETCH CONTROL WORD
DATA 4
DATA 3
RTI 2 RTI 2
DATA 2
RTI 2
DATA 1
RTI 2 RTI 2
* STATUS
FETCH DATA WORD #2
FETCH DATA WORD#1
FETCH DATA POINTER
FETCH COMMAND WORD
FETCH CONTROL WORD
TIME OUT TO 400 m
s
Figure 19. Bus Controller Scenario
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 12µs.
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
BCRTMP DMA
ACTIVITY
STATUS
FETCH COMMAND WORD #2
INTERRUPT
FETCH DATA POINTER
FETCH COMMAND WORD #1
FETCH CONTROL WORD
START BCRTMP
INITIALIZE REGISTERS
RTI
BC
CMD #1 CMD #2
BC
STORE DATA WORD#4
BCRTMP DMA
ARBITRATION3
FETCH COMMAND WORD #2
MANCHESTER
DATA BUS B
*
STORE STATUS WORD #1
DATA 2
BC
STORE DATA WORD#1
DATA1
BC
STORE DATA WORD #2
CMD
RTI 1
* STATUS
DATA 4
STORE DATA WORD#3
DATA 3
RTI 2
STORE DATA WORD#4
DATA 2
RTI 2 RTI 2
STORE STATUS WORD #1
484 to
492µs
STATUS DATA1
RTI 2 RTI 2
AUTO RETRY
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
EOL IN CONTROL WORD
SO STOP BCRTMP
STORE INTERRUPT STATUS WORD
BIT TIMES
1
2
3
4
5
COMMAND WORD
6
7
8
5
SYNC
REMOTE TERMINAL
ADDRESS
9
10
11
12
1
13
14
15
16
5
18
19
20
5
SUBADDRESS/
MODE
T/R
17
1
DATA WORD
COUNT/MODE CODE
P
DATA WORD
SYNC
DATA
P
PARITY
TERMINAL FLAG
SUBSYSTEM FLAG
DYNAMIC BUS CONTROL ACCEPTANCE
Figure 19. MIL-STD-1553B Word Formats
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
DC supply voltage
-0.3 to +7.0
V
VI/O
Voltage on any pin
-0.3 to V DD +0.3
V
II
DC input current
T STG
Storage temperature
T JMAX
Maximum junction temperature
PD
Average power dissipation 1
ΘJC
Thermal resistance, junction to-case
VDD
±10
mA
-65 to + 150
°C
+ 175
°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
BCRT-37
11.0 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 with pull-up resistors
Inputs with pull-up resistors
VIN = VDD or V SS
VIN = VDD
VIN = VSS
VOL
Low-level output voltage
TTL outputs
IOL = 3.2mA
V OH
High-level output voltage
TTL outputs
IOH = -400µA
2.4
I OZ
Three-state output leakage current
TTL outputs
VOUT = VDD or V SS
-10
VDD = 5.5V, VOUT = VDD
VDD = 5.5V, VOUT = 0V
-110
0.8
2.0
IOS
Short-circuit output current
CIN
Input capacitance
COUT
CIO
IDD
QIDD
3
Bidirect I/O capacitance
3
Average operating current
Quiescent current
1, 2
3
Output capacitance
MAXIMUM
1, 4
-1
-1
-550
UNIT
V
V
-1
-1
-80
µA
µA
µA
0.4
V
V
10
µA
110
mA
mA
ƒ = 1MHz @ 0V
15
pF
ƒ = 1MHz @ 0V
20
pF
ƒ = 1MHz @ 0V
25
pF
50
mA
1
mA
35
µA
ƒ = 12MHz, C L = 50pF
See Note 5, Tc =
-55oC
Tc = 25oC
+125 o C
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.
BCRT-38
11.0 AC ELECTRICAL CHARACTERISTICS
(OVER RECOMMENDED OPERATING CONDITIONS)
VIH MIN
ta
IN-PHASE
OUTPUT
OUT-OF-PHASE
OUTPUT
VIH MIN
VIL MAX
1
1
INPUT V IL MAX
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
PARAMETER
ta
tb
tc
td
te
tf
tg
INPUT↑
INPUT↑
INPUT↑
th
INPUT↑
INPUT↓
INPUT↓
INPUT↓
INPUT↑
to response↑
to response↓
to response↓
to response↑
to data valid
to high Z
to high Z
to data valid
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)
3V
90%
Device under
Test
90%
VREF
•
10%
10%
50pF
0V
IREF (sink)
< 2ns
< 2ns
Input Pulses
Output Loading
Note:
50pF including scope probe and test socket
Figure 21. AC Test Loads and Input Waveforms
BCRT-39
DMA GRANT RECOGNIZED ON THIS EDGE
MCLKD2
tSHL1
DMAR
DMAG
tPW2
DMACK
TSCTL
MEMCSO
ADDRESS
DATA
RWR/RRD
(2)
AEN
BURST
tPHL1
tOOZL1
t PZL1
tPHL2
tPHL3
tHLH2
tPHL4
SYMBOL
tSHL16
tPHL1
PARAMETER
DMACK↓ to DMAR High Impedance
MIN
0
0
2xMCLK
0
THMC1-10
MCLK-20
MCLK
-10
0
MAX
10
45
4xMCLK
UNITS
ns
ns
ns
ns
ns
ns
ns
DMAG↓ to DMACK↓ 3
tPHL21
DMAG↓ to TSCTL↓
tPZL16
TSCTL↓ to ADDRESS valid
40
tHLH2
RWR/RRD↑ to DMACK↑
THMC1+10
tPHL3
TSCTL↓ to RWR/RRD↓
MCLK+20
tPW21
DMAG↓ to DMAG↑
6xMCLK
tOOZL1
DMAR↓ to BURST↑
10
ns
tPHL4
DMAR↓ to DMAG↓ 5
3.5 (1.9)
µs
tPHL4
DMAR↓ to DMAG↓ 4
0
1.9 (0.8)
µs
Notes:
1. Guaranteed by test.
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 MCL
KD2 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
BCRT-40
tPLH1
t IOHL1
THMC1
THMC2
MCLK
MCLKD2
TSCTL
MEMCSO
tPLH2
tHLZ2
ADDRESS
DATA
RRD
tSHL1
SYMBOL
tSHL1
tSLH1
t PW1
PARAMETER
ADDRESS valid to RRD↓
tHLZ1
MIN
(ADDRESS setup) THMC2-10
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
UNITS
ns
MCLK-10
MCLK+5
ns
THMC1-10
THMC1+10
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)
BCRT-41
MAX
THMC2-15
tPLH1
tIOHL1
THMC1
THMC2
MCLK
MCLKD2
TSCTL
MEMCSO
tPLH2
tHLZ2
ADDRESS
DATA
RWR
tSHL1
tSLH1
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+5
RWR↓ to DATA valid
30
0
RWR↑ to DATA High Impedance
(DATA hold)
THMC1-10 THMC1+10
RWR↑ to ADDRESS High Impedance (ADDRESS hold) THMC1-10 THMC1+10
RWR↓ to RWR↑
MCLK-10 MCLK+5
MCLK↑ to MCLKD2↑
0
40
MCLK↑ to TSCTL/MEMCSO↓
0
40
MCLK↑ to RWR↓
0
60
UNITS
ns
ns
ns
ns
ns
ns
ns
ns
Note:
1. Guaranteed by test.
Figure 24. BCRT DMA Write Timing (One-Word Write)
BCRT-42
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
MIN
(DATA hold)
(DATA access)
(ADDRESS hold)
RD+CS↓ to RD+CS↑
RD+CS↑ to RD+CS↓
5
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
PARAMETER
tSHL1
ADDRESS valid to WR+CS↓
tSHL2
DATA valid to WR+CS↓
tPW1
WR+CSØ to WR+CS↑
tHLH1
WR+CS↑ to DATA High Impedance
tHLH2
WR+CS↑ to ADDRESS High Impedance
tPW2
WR+CS↑ to WR+CS↓
Notes:
1. Guaranteed by functional test.
MIN
(ADDRESS setup)
(DATA setup)
(DATA hold)
(ADDRESS hold)
Figure 26. BCRT Register Write Timing
BCRT-43
60
5
60
10
10
80
MAX
-
UNITS
ns
ns
ns
ns
ns
ns
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
UNITS
0
0
30
30
ns
ns
0
30
ns
Figure 27. BCRT Dual-Port Interface Timing Delays
tPZL1
MANCHESTER C
D
D
DMA
ACTIVITY
SYMBOL
tPZL11, 2
PARAMETER
Data word to DMA activity
MIN
0
MAX
UNITS
4
µs
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)
BCRT-44
tPLH2
MCLK
MCLKD2
DMAR
DMAG
DMAGO
DMACK
t SHL1
tPLH1
SYMBOL
PARAMETER
MAX
UNITS
0
30
ns
DMACK↓ to DMAR High Impedance
0
10
ns
MCLK↑ to MCLKD2↑
0
40
ns
tPLH11
DMAG↓ to DMAGO↓
tSHL1
tPLH2
MIN
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
BCRT-45
DMAR
DMAG
DMACK
RWR
RRD
TSCTL
BURST
STDINTL
STDINTP
tOOHL1
tOOLH1
tOOHL2
SYMBOL
tOOLH1
PARAMETER
TSCTL↑ to STDINTP/STDINTL↓
tPW1
STDINTP↓ to STDINTP↑
tOOHL1
DMACK↓ to RWR↓
tOOHL2
DMAG↓ to STDINTL↓
tPW1
MIN
MAX
UNITS
-
1
µs
340
ns
320
3xMCLK-10
8xMCLK
5xMCLK
10xMCLK
ns
µs
Note:
Address and data bus relationships (not shown) are identical to figure 22.
Figure 30. BCRT Interrupt Log List Entry Operation Timing
BCRT-46
TIMERON
11 10
9
8
7
6
5
4
3
2
1
D10
D11
D12
D13
D14
D15
BCRTF
BCRTSEL
MRST
D0
D1
D2
D3
D4
D5
D6
D7
VSS
VDD
D8
D9
12.0 PACKAGE OUTLINE DRAWINGS
84 83 82 81 80 79 78 77 76 75
LOCK
TAZ
TAO
RAZ
RAO
TBZ
TBO
RBZ
RBO
CLK
VSS
VDD
EXTOVR
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
TIMERON
CHA/B
COMSTR
25
61
26
60
27
59
RTA0
RTA1
RTA2
RTA3
RTA4
28
58
29
57
30
56
31
55
32
54
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 and LCC Pin Identification (Top View)
(Flatpack Leads Omitted for Clarity)
BCRT-47
BURST
TEST
SSYSF
MCLKD2
HPINT
STDINTP
STDINTL
DMAGO
AEN
MCLK
VDD
VSS
CS
RD
WR
MEMCSI
DMACK
DMAG
DMAR
TSCTL
MEMCSO
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
CLK
VSS
A0
A2
H
D3
D2
A3
A4
G
D6
D5
D4
A5
A6
A7
F
D7
D10
V
VSS
VDD
V SS
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
MRST
MCLK
4
DMAGO
VDD
DD
V
VSS
CHA/B
WR
SS
RD
DMACK
TSCTL
MEMCSO
A15
RRD
AEN
STDINTL
CS
MEMCSI
DMAG
DMAR
5
6
7
8
9
10
11
INDEX
CORNER
Figure 31b. BCRT Pingrid Array Pin Indentification (Bottom View)
BCRT-48
Package Selection Guide
RTI
24-pin DIP
(single cavity)
36-pin DIP
(dual cavity)
68-pin PGA
84-pin PGA
144-pin PGA
84-lead LCC
36-lead FP
(dual cavity)
(50-mil ctr)
84-lead FP
132-lead FP
RTMP
RTR
Product
BCRT BCRTM BCRTMP
RTS
XCVR
X
X
X
X
X
X
X
X1
X
X1
X
X
X
X
X
X
X
NOTE:
1. 84LCC package is not available radiation-hardened.
Packaging-1
D
1.565 ± 0.025
A
0.130 MAX.
-A-
Q
0.050 ± 0.010
0.040 REF.
0.080 REF.
(2 Places)
A
L
0.130 ±0.010
0.100 REF.
(4 Places)
E
1.565 ± 0.025
-B-
PIN 1 I.D.
(Geometry Optional)
e
0.100
TYP.
TOP VIEW
-CA
(Base Plane)
b
0.018 ± 0.002
0.030 C A B
0.010 C 2
R
SIDE VIEW
P
N
M
L
K
J
D1/E1
1.400
H
G
F
E
D
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
PIN 1 I.D.
(Geometry Optional)
BOTTOM VIEW
0.003 MIN. TYP.
Notes:
1. True position applies to pins at base plane (datum C).
2. True position applies at pin tips.
3. All package finishes are per MIL-M-38510.
4. Letter designations are for cross-reference to MIL-M-38510.
144-Pin Pingrid Array
Packaging-2
1
D/E
1.525 ± 0.015 SQ.
D1/E1
0.950 ± 0.015 SQ.
A
0.110
0.006
A
PIN 1 I.D.
(Geometry
Optional)
e
0.025
SEE DETAIL A
A
LEAD KOVAR
TOP VIEW
C
0.005 + 0.002
- 0.001
L
0.250
MIN.
REF.
S1
0.005 MIN. TYP.
SIDE VIEW
0.018 MAX. REF.
0.014 MAX. REF.
(At Braze Pads)
DETAIL A
BOTTOM VIEW A-A
Notes:
1. All package finishes are per MIL-M-38510.
2. Letter designations are for cross-reference to MIL-M-38510.
132-Lead Flatpack (25-MIL Lead Spacing)
Packaging-3
A
0.115 MAX.
D/E
1.150 ± 0.015 SQ.
A1
0.080 ± 0.008
A
PIN 1 I.D.
(Geometry Optional)
TOP VIEW
SIDE VIEW
L/L1
0.050 ± 0.005 TYP.
h
0.040 x 45_
REF. (3 Places)
B1
0.025 ± 0.003
e
0.050
J
0.020 X 455 REF.
e1
0.015 MIN.
PIN 1 I.D.
(Geometry Optional)
BOTTOM VIEW A-A
Notes:
1. All package finishes are per MIL-M-38510.
2. Letter designations are for cross-reference to MIL-M-38510.
84-LCC
Packaging-4
A
D/E
1.810 ± 0.015 SQ.
D1/E1
1.150 ± 0.012 SQ.
A
0.110
0.060
PIN 1 I.D.
(Geometry
Optional)
A
e
0.050
b
0.016 ± 0.002
SEE DETAIL A
A
LEAD KOVAR
C
0.007 ± 0.001
TOP VIEW
L
0.260
MIN.
REF.
S1
0.005 MIN. TYP.
SIDE VIEW
0.018 MAX. REF.
0.014 MAX.
REF.
(At Braze Pads)
BOTTOM VIEW A-A
DETAIL A
Notes:
1. All package finishes are per MIL-M-38510.
2. Letter designations are for cross-reference to MIL-M-38510.
84-Lead Flatpack (50-MIL Lead Spacing)
Packaging-5
D
1.100 ± 0.020
A
0.130 MAX.
-A-
Q
0.050 ± 0.010
A
L
0.130 ± 0.010
E
1.100 ± 0.020
PIN 1 I.D.
(Geometry Optional)
-B-
-C(Base Plane)
TOP VIEW
e
0.100
TYP.
0.030 C A B
0.010 C 2
SIDE VIEW
L
K
J
H
G
D1/
1.000
F
E
D
1
A
b
0.018 ± 0.002
2
3
4
5
6
7
8 9 10 11
PIN 1 I.D.
(Geometry Optional)
BOTTOM VIEW A-A
0.003 MIN.
Notes:
1. True position applies to pins at base plane (datum C).
2. True position applies at pin tips.
3. All packages finishes are per MIL-M-38510.
4. Letter designations are for cross-reference to MIL-M-38510.
84-Pin Pingrid Array
Packaging-6
1
D
1.100 ± 0.020
A
0.130 MAX.
Q
0.050 ± 0.010
-A-
A
L
0.130 ± 0.010
E
1.100 ± 0.020
-B-
PIN 1 I.D.
(Geometry Optional)
A
-C(Base Plane)
TOP
b
0.010 ± 0.002
∅ 0.030 C A B
∅ 0.010 C 2
e
0.100
TYP.
1
SIDE VIEW
L
K
J
H
G
F
E
D
C
B
A
D1/E1
1.00
1 2 3 4 5 6
PIN 1 I.D.
(Geometry Optional)
7
8
9
10 11
0.003 MIN. TYP.
BOTTOM VIEW A-A
Notes:
1 True position applies to pins at base plane (datum C).
2 True position applies at pin tips.
3. All packages finishes are per MIL-M-38510.
4. Letter designations are for cross-reference to MIL-M-38510.
68-Pin Pingrid Array
Packaging-7
E
0.750 ± 0.015
L
0.490
MIN.
b
0.015 ± 0.002
D
1.800 ± 0.025
e
0.10
PIN 1 I.D.
(Geometry Optional)
TOP VIEW
c
0.008
+ 0.002
- 0.001
A
0.130 MAX.
END VIEW
Notes:
1 All package finishes are per MIL-M-38510.
2. It is recommended that package ceramic be mounted to
a heat removal rail located on the printed circuit board.
A thermally conductive material such as MERECO XLN-589 or
equivalent should be used.
3. Letter designations are for cross-reference to MIL-M-38510.
36-Lead Flatpack, Dual Cavity (100-MIL Lead Spacing)
Packaging-8
Q
0.080 ± 0.010
(At Ceramic Body)
E
0.700 + 0.015
L
0.330
MIN.
b
0.016 + 0.002
D
1.000 ± 0.025
e
0.050
PIN 1 I.D
(Geometry Optional)
TOP
+ 0.002
c
0.007 - 0.001
A
0.100 MAX.
END
Q
0.070 + 0.010
(At Ceramic Body)
Notes:
1. All package finishes are per MIL-M-38510.
2. It is recommended that package ceramic be mounted to
a heat removal rail located on the printed circuit board.
A thermally conductive material such as MERECO XLN-589
or equivalent should be used.
3. Letter designations are for cross-reference to MIL-M-38510.
36-Lead Flatpack, Dual Cavity (50-MIL Lead Spacing)
Packaging-9
E
0.590 ± 0.012
S1
0.005 MIN.
S2
0.005 MAX.
e
0.100
D
1.800 ± 0.025
b
0.018 ± 0.002
PIN 1 I.D.
(Geometry Optional)
TOP VIEW
C
0.010 +- 0.002
0.001
E1
0.600 + 0.010
(At Seating Plane)
A
0.155 MAX.
L/L1
0.150 MIN.
SIDE VIEW
Notes:
1. All package finishes are per MIL-M-38510.
2. It is recommended that package ceramic be mounted to
a heat removal rail located on the printed circuit board.
A thermally conductive material such as MERECO XLN-589
or equivalent should be used.
3. Letter designations are for cross-reference to MIL-M-38510.
END VIEW
36-Lead Side-Brazed DIP, Dual Cavity
Packaging-10
E
0.590 ± 0.015
S1
0.005 MIN.
S2
0.005 MAX.
e
0.100
D
1.200 ± 0.025
b
0.018 ± 0.002
PIN 1 I.D.
(Geometry Optional)
TOP VIEW
+ 0.002
C
0.010 - 0.001
E1
0.600 + 0.010
(At Seating Plane)
L/L1
0.150 MIN.
A
0.140 MAX.
SIDE VIEW
Notes:
1. All package finishes are per MIL-M-38510.
2. It is recommended that package ceramic be mounted to
a heat removal rail located on the printed circuit board.
A thermally conductive material such as MERECO XLN-589 or
equivalent should be used.
3. Letter designations are for cross-reference to MIL-M-38510.
END VIEW
24-Lead Side-Brazed DIP, Dual Cavity
Packaging-11
ORDERING INFORMATION
UT1553B BCRT Bus Controller/Remote Terminal/Monitor: S
5962
*
*
*
*
*
Lead Finish:
(A) = Solder
(C) = Gold
(X) = Optional
Case Outline:
(X) = 84 pin PGA
(Y) = 84 pin FP
(Z) = 84 pin LCC (solder only)
(T) = 132 FP (.025 pitch, NCS)
Class Designator:
(-) = Blank or No field is QML Q
(V) = Class V
Drawing Number: 8862801
Total Dose:
(-) = None
Federal Stock Class Designator: No options
Notes:
1. Lead finish (A, C, or X) must be specified.
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. For QML Q product, the Q designator is intentionally left blank in the SMD number (e.g. 5962-8862801Q1YX).
4. 84 LCC only available with solder lead finish.
UT1553B BCRT Bus Controller/Remote Terminal/Monitor
UT1553B/
BCRT- *
*
*
*
Total Dose:
()
= None
Lead Finish:
(A) = Solder
(C) = Gold
(X) = Optional
Screening:
(C) = Military Temperature
(P) = Prototype
Package Type:
(A) = 84pin LCC (solder only)
(G) = 84 pin PGA
(W) = 84 pin FP
(F) = 132 FP (0.25 pitch, NCS)
UTMC Core Part Number
Notes:
1. Lead finish (A, C, or X) must be specified.
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. Mil Temp range flow per UTMC’s manufacturing flows document. Devices are tested at -55°C, room temperature, and 125°C. Radiation neither tested
nor guaranteed.
4. Prototpe flow per UTMC’s document manufacturing flows and are tested at 25°C only. Radiation characteristics neither tested nor guaranteed. Lead
finish is GOLD only.
5. 84 LCC only available with solder lead finish.