UT1553 BCRTM p Register-oriented architecture to enhance FEATURES p Comprehensive MIL-STD-1553 dual-redundant Bus p p p p p programmability p DMA memory interface with 64K addressability p Internal self-test p Radiation-hardened option available for 84-lead Controller (BC) and Remote Terminal (RT) and Monitor (M) functions MIL-STD-1773 compatible Multiple message processing capability in BC Time tagging and message logging in RT and M modes Automatic polling and intermessage delay in BC mode Programmable interrupt scheme and internally generated interrupt history list flatpack package only p Remote terminal operations in ASD/ENASD-certified (SEAFAC) p Available in 84-pin pingrid array, 84-lead flatpack, 84lead leadless chip-carrier p Standard Microcircuit Drawing 5962-89577 available - QML Q and V compliant REGISTERS CONTROL MASTER RESET 12MHz STATUS HIGH-PRIORITY STD PRIORITY LEVEL STD PRIORITY PULSE CURRENT BC (or M) BLOCK/ RT DESCRIPTOR SPACE POLLING COMPARE INTERRUPT HANDLER CLOCK & RESET LOGIC 1553 DATA CHANNEL A 1553 DATA CHANNEL B TIMERON DUAL CHANNEL ENCODER/ DECODER MODULE CURRENT COMMAND PARALLELTO-SERIAL CONVERSION ADDRESS GENERATOR INTERRUPT LOG LIST POINTER BC PROTOCOL & MESSAGE HANDLER HIGH-PRIORITY INTERRUPT ENABLE BUS TRANSFER LOGIC 16 SERIAL-TOPARALLEL CONVERSION TIMEOUT BUILT-IN-TEST WORD HIGH-PRIORITY INTERRUPT STATUS 16 STANDARD INTERRUPT ENABLE 16 RT/MONITOR PROTOCOL & MESSAGE HANDLER 16 DMA/CPU CONTROL 16 RT ADDRESS BUILT-IN-TEST START COMMAND 16 BUILTINTEST RESET COMMAND RT TIMER RESET COMMAND MONITOR ADDRESS CONTROL MONITOR ADDRESS SELECT (0-15) DMA ARBITRATION REGISTER CONTROL ADDRESS MONITOR ADDRESS SELECT (16-31) DUAL-PORT MEMORY CONTROL 16 Figure 1. BCRTM Block Diagram 16 DATA BCRTM-1 Table of Contents 1.0 INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 1.1 1.2 1.3 2.0 PIN IDENTIFICATION AND DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 3.0 INTERNAL REGISTERS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 4.0 SYSTEM OVERVIEW . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 5.0 SYSTEM INTERFACE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 5.1 5.2 5.3 5.4 5.6 6.0 6.2 6.3 7.0 RT Functional Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24 6.1.1 RT Subaddress Descriptor Definitions . . . . . . . . . . . . . . . . . . . . . . . . . .24 6.1.2 Message Status Word . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25 6.1.3 Mode Code Descriptor Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26 RT Error Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28 RT Operational Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28 BUS CONTROLLER ARCHITECTURE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 7.1 7.2 7.3 7.4 7.5 8.0 DMA Transfers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20 Hardware Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21 CPU Interconnection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21 RAM Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23 Transmitter/Receiver Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23 REMOTE TERMINAL ARCHITECTURE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 6.1 BC Functional Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30 Polling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31 BC Error Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31 BC Operational Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32 BC Operational Example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33 MONITOR ARCHITECTURE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 8.1 8.2 8.3 BCRTM-2 Features - Remote Terminal (RT) Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3 Features - Bus Controller (BC) Mode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3 Features - Monitor (M) Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4 Monitor Functional Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35 Monitor Error Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35 Monitor Operational Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35 9.0 EXCEPTION HANDLING AND INTERRUPT LOGGING . . . . . . . . . . . . . . . . . . . . . . . . 36 10.0 MAXIMUM AND RECOMMENDED OPERATING CONDITIONS . . . . . . . . . . . . . . . . 40 11.0 DC ELECTRICAL CHARACTERISTICS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 12.0 AC ELECTRICAL CHARACTERISTICS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 13.0 PACKAGE OUTLINE DRAWINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51 1.0 INTRODUCTION The monolithic CMOS UT1553 BCRTM provides the system designer with an intelligent solution to MIL-STD-1553B multiplexed serial data bus design problems. The UT1553B BCRTM is a single-chip device that implements all three of defined MIL-STD-1553B functions - Bus Controller, Remote Terminal, and Monitor. Designed to reduce host CPU overhead, the BCRTM’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 BCRTM uses a linked-list message scheme to provide the host with message chaining capability. The BCRTM enhances memory use by supporting variable-size, relocatable data blocks. In the RT mode, the BCRTM implements time-tagging and message history functions. It also supports multiple (up to 128) message buffering and variable length messages to any subaddress.In the Monitor (M) mode, the BCRTM’s powerful linked list command block structure allows it to process a series of monitored 1553 messages without the intervention of the host. The BCRTM can store as much bus traffic as can be contained in its 64K memory space. In addition, the host has the capability of instructing the BCRTM to monitor and store data for only selected remote terminals. The UT1553 BCRTM is an intelligent, versatile, and easy to implement device -- a powerful asset to system designers. 1.1 Features - Remote Terminal (RT) Mode Indexing The BCRTM is programmable to index or buffer messages on a subaddress-by-subaddress basis. The BCRTM, 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. Variable Space Allocation The BCRTM can use as little or as much memory (up to 64K) as needed. Selectable Data Storage Address programmability within the BCRTM provides flexible data placement and convenient access. Sequential Data Storage The BCRTM stores/retrieves, by subaddress, all messages in the order in which they are transacted. Sequential Message Status Information The BCRTM provides message validity, time-tag, and word-count information, and stores it sequentially in a separate, cross-referenced list. Illegalizing Mode Codes and Subaddresses The host can declare mode codes and subaddresses illegal by setting the appropriate bit(s) in memory. 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 BCRTM 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 BCRTM 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 BCRTM can delay a host-specified time before executing the next message in sequence. Automatic Polling When polling, the BCRTM interrogates the remote terminals and then compares their status word responses to the contents of the Polling Compare Register. The BCRTM can interrupt the host CPU if an erroneous remote terminal status word response occurs. Automatic Retry The BCRTM can automatically retry a message on busy, message error, and/or response time-out conditions. The BCRTM can retry up to four times on the same or on the alternate bus. 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 BCRTM provides an Interrupt History List that records, in the order of occurrence, the events that caused the interrupts. The list length is programmable. Variable Space Allocation The BCRTM uses as little or as much memory (up to 64K) as needed. Selectable Data Storage Address programmability within the BCRTM provides flexible data placement and convenient access. BCRTM-3 1.3 Features - Monitor (M) Mode Command History List The BCRTM’s linked list command block structure permits the BCRTM to process a series of monitored messages without host intervention. Monitor Selected Terminal Address The host can select the remote terminals to be monitored by programming the proper bits in the Terminal Address Select registers (Registers16 and 17). The BCRTM can monitor any or all remote terminals. Variable Space Allocation The BCRTM can use as little or as much memory (up to 64K) as needed BCRTM-4 Selectable Data Storage Address programmability within the BCRTM provides flexible data placement and convenient access. Sequential Data Storage The BCRTM stores, by Terminal Address, all 1553 messages in the order in which they are transacted. Programmable Interrupt Selection The host can select a wide variety of events that may cause an interrupting event. Interrupt History List The BCRTM stores, chronologically in memory, an Interrupt History List of each event that causes an interrupt. 2.0 PIN IDENTIFICATION AND DESCRIPTION BIPHASE OUT TAZ TAO TBZ TBO 13 14 17 18 (K3) (L2) (L4) (K6) BIPHASE IN RAZ RAO RBZ RBO 15 16 19 20 (L3) (K4) (K5) (L5) TERMINAL ADDRESS RTA0 RTA1 RTA2 RTA3 RTA4 RTPTY 28 29 30 31 32 33 (K8) ** (L9) ** (L10) ** (K9) ** (L11) ** (K10) ** STATUS SIGNALS STDINTL STDINTP HPINT TIMERON COMSTR SSYSF BCRTF CHA/B TEST 68 69 70 25 27 72 75 26 73 (A6) + (A4) (B4) + (K7) (L8) (A2) (B2) (J7) (B3)* DMAR DMAG DMAGO DMACK BURST TSCTL 56 57 67 58 74 55 (A10) + (A9) (B5) (B8) + (A1) (B9) DMA SIGNALS RD WR CS AEN BCRTSEL LOCK CONTROL MRST SIGNALS EXTOVR RRD RWR MEMCSI MEMCSO ** + ++ * Pin internally pulled up. Pin at high impedance when not asserted Bidirectional pin. Formerly MEMWIN. 61 60 62 66 11 12 10 24 53 52 59 54 (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 array pin identification in parentheses. LCC, flatpack pin number not in parentheses. Figure 2. BCRT Functional Pin Description BCRTM-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. NAME PIN NUMBER LCC PGA A0 34 A1 TYPE ACTIVE J10 TTB -- Bit 0 (LSB) of the Address bus 35 K11 TTB -- Bit 1 of the Address bus A2 36 J11 TTB -- Bit 2 of the Address bus A3 37 H10 TTB -- Bit 3 of the Address bus A4 38 H11 TTB -- Bit 4 of the Address bus A5 39 G9 TTO -- Bit 5 of the Address bus A6 40 G10 TTO -- Bit 6 of the Address bus A7 41 G11 TTO -- Bit 7 of the Address bus A8 44 E9 TTO -- Bit 8 of the Address bus A9 45 E11 TTO -- Bit 9 of the Address bus A10 46 E10 TTO -- Bit 10 of the Address bus A11 47 F11 TTO -- Bit 11 of the Address bus A12 48 D11 TTO -- Bit 12 of the Address bus A13 49 D10 TTO -- Bit 13 of the Address bus A14 50 C11 TTO -- Bit 14 of the Address bus A15 51 B11 TTO -- Bit 15 (MSB) of the Address bus BCRTM-6 DESCRIPTION DATA BUS NAME PIN NUMBER LCC PGA TYPE ACTIVE DESCRIPTION D0 9 K1 TTB -- Bit 0 (LSB) of the Data bus D1 8 J1 TTB -- Bit 1 of the Data bus D2 7 H2 TTB -- Bit 2 of the Data bus D3 6 H1 TTB -- Bit 3 of the Data bus D4 5 G3 TTB -- Bit 4 of the Data bus D5 4 G2 TTB -- Bit 5 of the Data bus D6 3 G1 TTB -- Bit 6 of the Data bus D7 2 F1 TTB -- Bit 7 of the Data bus D8 83 E1 TTB -- Bit 8 of the Data bus D9 82 E2 TTB -- Bit 9 of the Data bus D10 81 F2 TTB -- Bit 10 of the Data bus D11 80 D1 TTB -- Bit 11 of the Data bus D12 79 D2 TTB -- Bit 12 of the Data bus D13 78 C1 TTB -- Bit 13 of the Data bus D14 77 B1 TTB -- Bit 14 of the Data bus D15 76 C2 TTB -- Bit 15 (MSB) of the Data bus TYPE ACTIVE TERMINAL ADDRESS INPUTS NAME PIN NUMBER LCC PGA RTA0 28 K8 TUI -- Remote Terminal Address Bit 0 (LSB). The entire RT address is strobed in at Master Reset. Verify it by reading the Remote Terminal Address Register. All the Remote Terminal Address bits are internally pulled up. RTA1 29 L9 TUI -- Remote Terminal Address Bit 1. This is bit 1 of the Remote Terminal Address. RTA2 30 L10 TUI -- Remote Terminal Address Bit 2. This is bit 2 of the Remote Terminal Address. RTA3 31 K9 TUI -- Remote Terminal Address Bit 3. This is bit 3 of the Remote Terminal Address. RTA4 32 L11 TUI -- Remote Terminal Address Bit 4. This is bit 4 (MSB) of the Remote Terminal Address. RTPTY 33 K10 TUI -- Remote Terminal (Address) Parity. This is an odd parity input for the Remote Terminal Address. DESCRIPTION BCRTM-7 CONTROL SIGNALS NAME PIN NUMBER LCC PGA TYPE ACTIVE DESCRIPTION RD 61 B7 TI AL Read. The host uses this in conjunction with CS to read an internal BCRTM register. WR 60 C7 TI AL Write. The host uses this in conjunction with CS to write to an internal BCRTM register. CS 62 A7 TI AL Chip Select. This selects the BCRTM when accessing the BCRTM’s internal register. AEN 66 A5 TI AH Address Enable. The host CPU uses AEN to indicate to the BCRTM that the BCRTM’s address lines can be asserted; this is a precautionary signal provided to avoid address bus crash. If not used, it must be tied high. BCRTSEL 11 L1 TUI -- LOCK 12 K2 TUI AH EXTOVR 24 L7 TUI AL MRST 10 J2 TI AL MEMCSO 54 B10 TO AL MEMCSI 59 A8 TUI AL Memory Chip Select In. Used in the pseudo-dual-port RAM mode only, MEMCSI is received from the host and is propagated through to the MEMCSO. RRD 53 A11 TO AL RAM Read. In the pseudo-dual-port RAM mode, the host uses this signal in conjunction with MEMCSO to read from external RAM through the BCRTM. It is also the signal the BCRTM uses to read from memory. It is asserted following receipt of DMAG. When the BCRTM performs multiple reads, this signal is pulsed. RWR 52 C10 TO AL RAM Write. In the pseudo-dual-port RAM mode, the CPU and BCRTM use this to write to external RAM. This signal is asserted following receipt of DMAG. For multiple writes, this signal is pulsed. BCRTM-8 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. When set, this pin prevents internal changes to both the RT address and BC/RT mode select functions. This pin is internally pulled high. External Override. Use this in multi-redundant applications. Upon receipt, the BCRTM aborts all current activity. EXTOVR should be connected to COMSTR output of the adjacent BCRTM when used. This pin is internally pulled high. Master Reset. This resets all internal state machines, encoders, decoders, and registers. The minimum pulse width for a successful Master Reset is 500ns. Memory Chip Select Out. This is the regenerated MEMCSI input for external RAM during the pseudodual-port RAM mode. The BCRTM also uses it to select external memory during memory accesses. STATUS SIGNALS NAME PIN NUMBER LCC PGA TYPE ACTIVE DESCRIPTION STDINTL 68 A6 TTO ZL Standard Interrupt Level. This is a level interrupt. It is asserted when one or more events enabled in either the Standard Interrupt Enable Register, RT Descriptor, or BC Command Block occur. Resetting the Standard Interrupt bit in the High-Priority Interrupt Status/Reset Register clears the interrupt. STDINTP 69 A4 TO AL Standard Interrupt Pulse. STDINTP pulses when an interrupt is logged. HPINT 70 B4 TTO ZL High Priority Interrupt. The High-Priority Interrupt level is asserted upon occurrence of events enabled in the High Priority Interrupt Enable Register. The corresponding bit(s) in the High-Priority Interrupt Status/Reset Register reset HPINT. TIMERON 25 K7 TO AL COMSTR 27 L8 TO AL SSYSF 72 A2 TI AH BCRTF 75 B2 TO AH CHA/B 26 J7 TO -- TEST 73 B3 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 channel A and B transmitters. (RT) Command Strobe. The BCRTM asserts this signal after receiving a valid command. The BCRTM deactivates it after servicing the command. Subsystem Fail. Upon receipt, this signal propagates directly to the RT 1553 status word and the BCRTM Status Register. 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. Channel A/B. This indicates the active or last active channel. TEST. This pin is used as a factory test pin. (Formerly MEMWIN.) BIPHASE INPUTS NAME PIN NUMBER LCC PGA TYPE ACTIVE DESCRIPTION RAO 16 K4 TI -- Receive Channel A One. This is the Manchester-en-coded true signal input from Channel A of the bus receiver RAZ 15 L3 TI -- Receive Channel A Zero. This is Manchester-encoded complementary signal input from Channel A of the bus receiver RBO 20 L5 TI -- Receive Channel B One. This is the Manchester-en-coded true signal input from Channel B of the bus receiver. RBZ 19 K5 TI -- Receive Channel B Zero. This is the Manchester-en-coded complementary signal input from Channel B of the bus receiver BCRTM-9 BIPHASE OUTPUTS NAME PIN NUMBER LCC PGA TYPE ACTIVE DESCRIPTION TAO 14 L2 TO -- Transmit Channel A One. This is the Manchester-encoded true output to be connected to the Channel A bus transmitter input. This signal is idle low. TAZ 13 K3 TO -- Transmit Channel A Zero. This is the Manchester-encoded complementary output to be connected to the Channel A bus transmitter input. This signal is idle low. TBO 18 K6 TO -- Transmit Channel B One. This is the Manchesterencoded true output to be connected to the Channel B bus transmitter input. This signal is idle low. L4 TO -- Transmit Channel B Zero. This is the Manchester-encoded complementary output to be connected to the Channel B bus transmitter input. This signal is idle low. TYPE ACTIVE DESCRIPTION TBZ 17 DMA SIGNALS NAME PIN NUMBER LCC PGA DMAR 56 A10 TTO ZL DMA Request. The BCRTM issues this signal when access to RAM is required. It goes inactive after receiving a DMAG signal. DMAG 57 A9 TI AL DMA Grant. This input to the BCRTM allows the BCRT to access RAM. It is recognized 45ns before the rising edge of MCLKD2. DMAGO 67 B5 TO AL DMA Grant Out. If DMAG is received but not needed, it passes through to this output. DMACK 58 B8 TTO ZL DMA Acknowledge. The BCRTM asserts this signal to confirm receipt of DMAG, it stays low until memory access is complete. BURST 74 A1 TO AH Burst (DMA Cycle). This indicates that the current DMA cycle transfers at least two words; worst case is five words plus a “dummy” word. TSCTL 55 B9 TO AL BCRTM-10 Three-State Control. This signal indicates when the BCRTM is actually accessing memory. The host subsystem’s address and data lines must be in the high-impedance state when the signals active. This signal assists in placing the external data and address buffers into the high-impedance state. CLOCK SIGNALS NAME PIN NUMBER LCC PGA TYPE ACTIVE DESCRIPTION CLK 21 J5 TI -- Clock. The 12MHz input clock requires a 50% ± 10% duty cycle with an accuracy of ± 0.01%. The accuracy is required in order to meet the Manchester encoding/ decoding requirements of MIL-STD-1553. MCLK 65 C5 TI -- Memory Clock. This is the input clock frequency the BCRTM uses for memory accesses. The memory cycle time is equal to two MCLK cycles. Therefore, RAM access time is dependent upon the chosen MCLK frequency (6MHz minimum, 12MHz maximum). Please see the BCRTM DMA timing diagrams in this data sheet. MCLKD2 71 A3 TO -- Memory Clock Divided by Two. This signal is the Memory Clock input divided by two. It assists the host subsystem in synchronizing DMA events. TYPE ACTIVE POWER AND NAME PIN NUMBER LCC PGA DESCRIPTION VDD 23 L6 PWR -- +5V VDD 43 F9 PWR -- +5V VDD 64 G13 PWR -- +5V VDD 84 C7 PWR -- +5V VSS 1 J3 GND -- Ground VSS 22 N8 GND -- Ground VSS 42 F10 GND -- Ground VSS 63 B6 GND -- Ground BCRTM-11 3.0 INTERNAL REGISTERS The BCRTM’s internal registers (see table 1 on pages 1819) enable the CPU to control the actions of the BCRTM while maintaining low DMA overhead by the BCRTM. 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 BIT 15 Reserved. BIT 14 Rt Address 31. When RT31=0, the BCRTM recognizes RT Address 31 as a Broadcast command. When RT31=1,the BCRTM treats RT Address 31 as a normal terminal address. BIT 13 Subaddress 31. When SA31=0, the BCRTM recognizes a command word with either subaddress 0 or 31 as being a valid code. When SA31=1, the BCRTM only recognizes a command word with a subaddress of 0 as a valid mode code. BIT 12 Bus Controller Time out. When the BCRTM is a BC and BCTO=0, the BCRTM allows an RT up to 16us to respond with a status word before it declares a bus time-out. If BCTO=1, the BCRTM allows an RT up to 32us to respond with a status word before it declares a bus time-out. In the remote terminal mode of operation, this bit controls to RT to RT response time-out. To support the requirements of MIL-STD-1553B, this bit is set to a logical zero. 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/Monitor 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/M modes. For monitor operation this bit must be "0". 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,M) Channel B Enable. When set, this bit enables Channel B operation. (BC) No significance. BIT 7 (RT,M) 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 29). 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 or M mode, It enables the BCRTM to receive a valid command. RT operation does not start until a valid command is received. When using this function: • • BCRTM-12 Restart the BCRTM after each Master Reset or programmed reset. This bit is not readable; verify operation by reading bit 0 of the BCRTM’s Status Register. #1 Status Register (Read Only) These bits indicate the BCRTM’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,M) Remote Terminal (or Monitor) Active. Indicates that the BCRTM, in the Remote Terminal (or Monitor) 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 16). 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 BCRTM has just received a Reset Remote Terminal (#01000) Mode Code. This bit remains set less than 1ms. 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,M)/Remote Terminal Descriptor Space Address Register (RT) (BC) This register contains the address of the head pointer of the Command Block being executed. Accessing a new Command Block updates it. (RT) The host CPU initializes this register to indicate the starting location of the RT Descriptor Space. The host must allocate 320 sequential locations following this starting address. For proper operation, this location must start on an I x 512 decimal address boundary, where I is an integer multiple. (M) This register contains the address of the control/status word of the current Monitor Command Block. Accessing a new Command Block updates it. #3 Polling Compare Register In the polling mode, the CPU sets the Polling Compare Register to indicate the RT response word on which the BCRTM 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 32). BCRTM-13 #4 BIT (Built-In-Test) Word Register The BCRTM uses the contents of this register when it responds to the Transmit BIT Word Mode Code (#10011). In addition, the BCRTM 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) to indicate a BIT failure. 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 BIT 15 BIT 14 BIT 13-0 Description Channel B failure. Channel A failure. BIT Word. The least significant fourteen bits of the BIT Word are user programmable. #5 Current Command Register (Read Only) In the RT or Monitor mode, this register contains the command currently being processed. When not processing a command, the BCRTM stores the last command or status word transmitted on the 1553B bus in this register. 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 BCRTM updates this register with the address of the next entry in the list. (See page 37.) #7 High-Priority Interrupt Enable Register (Read/Write) 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 BCRTM 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 BCRTM 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 formatted RT-RT Command Blocks. BIT 6 (RT) Dynamic Bus Control Mode Code Interrupt Enable. When set, an interrupt is asserted 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 BCRTM detected a BIT failure. BIT 2 (BC) End of Command Block List Enable (see Command Block Control Word, page 38.) 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 BCRTM 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 BCRTM’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 STDINTL pin is asserted when a Standard Interrupt occurs. BCRTM-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 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 BCRTM 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,M) Message Error Event. This bit enables a standard interrupt for message errors. BIT 0 (BC,M) 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. BCRTM-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 BCRTM 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 BCRTM receives the Dynamic Bus Control Mode Code from the currently active Bus Controller. Host intervention is required for the BCRTM to take over as the active Bus Controller. BIT 11 (RT) Terminal Flag. Setting this bit sets the RT status word Terminal Flag bit; the Terminal Flag bit in the RT status word is also internally set if the BIT fails. BIT 10 (RT) Service Request. Setting this bit sets the RT status word Service Request bit. BIT 9 (RT) Busy Mode Enable. Setting this bit sets the RT status word Busy bit and inhibits all data transfers to the subsystem. BIT 8 BC/RT Mode Select. This bit’s state reflects the external pin BCRTSEL. It does not necessarily reflect the state of the chip, since the BC/RT Mode Select is software-programmable via bit 10 of Register 0. This bit is read-only. BIT 7 Change Lock-Out. This bit’s state reflects the external pin LOCK. When set, this bit indicates that changes to the RT address or the BC/RT Mode Select are not allowed using internal registers. This bit is read-only. BIT 6 Remote Terminal Address Parity Error. This bit indicates a Remote Terminal Address Parity Error. It appears after the Remote Terminal Address is latched if a parity error exists. BIT 5 Remote Terminal Address Parity. This is an odd parity input bit used with the Remote Terminal Address. It ensures accurate recognition of the Remote Terminal Address. BITs 4-0 Remote Terminal Address (Bit 0 is the LSB). This reflects the RTA4-0 inputs at Master Reset. Modify the Remote Terminal Address by writing to these bits. #11 BIT Start Register (Write Only) Any write (i.e., data = don’t care) to this register’s address location initiates the internal BIT routine, which lasts 100µs. 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 BCRTM’s self-test performs an internal wrap-around test between its Manchester encoder and its two Manchester decoders. If the BCRTM 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 BCRTM 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 BCRTM 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. BCRTM-16 #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 BCRTM’s Remote Terminal Timer time-tags message transactions. The time tag is generated from a free-running eightbit timer of 64µs resolution. This timer can be reset to zero simply by writing to Register 13. When the timer is reset, it immediately starts running. #14 Activity Status/Operational Mode Register BIT 15 Bus Monitor Select. This bit should be cleared for RT mode operation. The host sets this bit to enable the BCRTM’s Monitor mode of operation. Bit 10 of Register 0 must also be "0" to enable the Monitor mode. BIT 14 Monitor All Terminals. When this bit is set, the BCRTM monitors all remote terminal activity.If this bit is not set, then bit 13 must be set. This bit should be cleared for RT Mode operation. BIT 13 Monitor Declared Terminals. When this bit is set, the BCRTM monitors all remote terminal bus activity. If this bit is not set, then bit 13 must be set.This bit should be cleared for RT mode operation. BITs 12-0 Reserved #15 Reserved Register This register is reserved for BCRTM use only and the host should not access it. #16 Monitor Selected Remote Terminal Address 15-0 BITs 15-0 Monitor Selected Remote Terminal Addresses 15-0. By setting the appropriate bit in this register, the host can determine which or the Remote terminals, from RT 0 through RT 15, the BCRTM will monitor. For example, by setting bit 5 in this register, the host instructs the BCRTM to only monitor the bus activity for remote terminal 5. These bits are not mutually exclusive, therefore, the host can monitor any number of different remote terminals by selecting the proper combination of bits. #17 Monitor Selected Remote Terminal Address 31-16 BITs 15-0 Monitor Selected Remote Terminal Addresses 31-16. By setting the appropriate bit in this register, the host can determine which or the Remote terminals, from RT 16 through RT 31, the BCRTM will monitor. For example, by setting bit 21 in this register, the host instructs the BCRTM to only monitor the bus activity for remote terminal 21. These bits are not mutually exclusive, therefore, the host can monitor any number of different remote terminals by selecting the proper combination of bits on this register and Register 16. BCRTM-17 #0 BC/RT CONTROL REGISTER 15 14 UNUSED 7 CHNSEL BUSAEN #1 4 3 2 1 0 RTYBCME RTYTO RTYME RTYBSY STEN 12 DYNBUS RT FLAG 11 BUSY 9 8 BIT RESET 4 3 2 1 0 UNUSED UNUSED UNUSED UNUSED CMBKPG (BC) CURRENT COMMAND BLOCK REGISTER (RT) REMOTE TERMINAL DESCRIPTOR SPACE ADDRESS REGISTER 15 14 13 12 11 A14 A13 A12 A11 10 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 13 12 D13 D12 11 D11 10 MSGERR 2 SS FLAG 10 D10 9 8 INSTR SRQ 1 0 DBC TF 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 BCRTM HIGH-PRIORITYINTERRUPT ENABLE REGISTER 15 14 13 12 11 UNUSED 7 6 ILLCMD DYNBUS UNUSED 5 SSFAIL UNUSED UNUSED UNUSED 7 6 ILLCMD DYNBUS UNUSED 5 SSFAIL 10 9 8 UNUSED UNUSED DATOVR 4 3 2 1 0 ENDBIT BITFAIL EOL MSGERR STDINT BCRTM HIGH-PRIORITYINTERRUPT STATUS/RESET REGISTER 15 14 13 12 11 UNUSED UNUSED 4 ENDBIT UNUSED 3 BITFAIL Table 1. BCRTM Registers BCRTM-18 10 SRQ 5 UNUSED #8 8 BUSBEN SSFAIL A15 #7 9 RTYALTB 6 D15 #6 13 10 BC/RT BUSA/B CHBFAIL #5 RTACT 11 EXTOVR 7 X #4 5 RTYCNT 12 BCTO BC/RT A15 #3 13 UNUSED 6 BC/RT STATUS REGISTER 15 14 TEST #2 UNUSED 10 9 8 UNUSED UNUSED DATOVR 2 1 0 EOL MSGERR STDINT #9 STANDARD INTERRUPT ENABLE REGISTER 15 14 13 12 UNUSED #10 #12 #13 #14 11 10 9 8 UNUSED UNUSED UNUSED UNUSED 6 5 4 3 UNUSED ILLBCMD ILLCMD POLMTCH REMOTE TERMINAL ADDRESS REGISTER 15 14 13 BUSY2 SS FLAG 12 DBC 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 12 11 10 9 8 X X X X X BUS MONITOR CONTROL REGISTER 15 14 13 MAT MDT 7 6 5 4 3 2 1 0 X X X X X X X X MONITOR SELECTED REMOTE TERMINAL ADDRESES 0-15 15 14 13 12 11 TA15 #17 UNUSED 7 BMS #16 UNUSED UNUSED INSTR #11 UNUSED TA14 TA13 TA12 TA11 10 9 8 TA10 TA9 TA8 7 6 5 4 3 2 1 0 TA7 TA6 TA5 TA4 TA3 TA2 TA1 TA0 MONITOR SELECTED REMOTE TERMINAL ADDRESES 16-31 15 14 13 12 11 10 9 8 TA31 TA30 TA29 TA28 TA27 TA26 TA25 TA24 7 6 5 4 3 2 1 0 T23 T22 T21 T20 T19 TA18 TA17 TA16 X = DON’T CARE Table 1. BCRTM Registers (continued from page 18) BCRTM-19 4.0 SYSTEM OVERVIEW The BCRTM can be configured for a variety of processor and memory environments. The host processor and the BCRTM 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 BCRTM control information -- message data, and status/ error information. Built-in memory management functions designed specifically for MIL-STD-1553 applications aid processor off-loading. The host needs only to establish the parameters within memory so the BCRTM can access this information as required. For example, in the RT mode, the BCRTM can store data associated with individual subaddresses anywhere within its 64K address space. The BCRTM 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 Monitor (M) mode, the BCRTM’s powerful linked list command block structure allows it to process a series of monitored 1553 messages without the intervention of the host. The BCRTM can store as much bus traffic as can be contained in its 64K memory space. In addition, the host has the capability of instructing the BCRTM to monitor and store data for only selected remote terminals. The host system is responsible for initializing an area in memory that tells the BCRTM where to store command word information and data for each command that the BCRTM receives on the 1553 bus. This area of memory consists of "Bus Monitor Command Blocks." An M Command Block is very similar to the BC Command Block in the BCRTM. The only real differences are the direction of information flow, and that there is no Head Pointer in the M Command Block. 5.0 SYSTEM INTERFACE 5.1 DMA Transfers The BCRTM 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 BCRTM to output an address onto the Address bus. RAM CPU MEMORY CONTROL SIGNALS RRD RWR MEMCSO BCRTM RD WR MEMCSI Figure 3a. Pseudo-Dual-Port RAM Control Signals BCRTM-20 In the BC mode, the BCRTM can process multiple messages, assist in scheduling message lists, and provide host-programmable functions such as auto retry. The BCRTM is incorporated in systems with a variety of interrupt latencies by using the Interrupt History List feature (see Exception Handling and Interrupt Logging, page 37). 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. The BCRTM requests transfer cycles by asserting the DMAR output, and initiates them when a DMAG input is received. A DMACK output indicates that the BCRTM has control of the Data and Address buses. The TSCTL output is asserted when the BCRTM is actually asserting the Address and Data buses. To support using multiple bus masters in a system, the BCRTM outputs the DMAGO signal that results from the DMAG signal passing through the chip when a BCRTM bus request was not generated (DMAR inactive). You can use DMAGO in daisy-chained multimaster systems. 5.2 Hardware Interface The BCRTM provides a simple subsystem interface and facilitates DMA arbitration. The user can configure the BCRTM to operate in a variety of memory-processor environments including 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 BCRTM’s Address and Data buses connect directly to RAM, with buffers isolating the BCRTM’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 BCRTM and connect to memory as RRD, RWR, and MEMCSO. Standard DMA Configuration The BCRTM’s and CPU’s data, address, and control signals are connected to each other as shown in figures 3c and 3d. The RWR, RRD, and MEMCSO are activated after DMAG is asserted. In either case, the BCRTM’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 BCRTM. CPU attempts to access BCRTM registers are ignored during BCRTM 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 BCRTM is accessing memory or when the CPU can access memory. AEN is also available (use is optional), giving the CPU control over the BCRTM’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. BUFFERS 16 DATA RAM HOST CPU 16 ADDRESS CONTROL BCRTM (DUAL REDUNDANT) DUAL TRANSCEIVER XFMR CONTROL/ARBITRATION TRANSMITTER TIMEOUT XFMR BUS A 1553 BUS BUS B Figure 3b. CPU/BCRTM Interface -- Pseudo-Dual-Port RAM Configuration BCRTM-21 ADDRESS BUS DMAR DMAG DMACK BCRTM CPU DATA BUS RRD RWR SHARED MEMORY AREA OE • WE • CS • MEMCSO Figure 3c. DMA Signals RAM DATA ADDRESS BCRTM MEMORY BUFFER CONTROL CPU ARBITRATION DUAL TRANSCEIVER XFMR XFMR BUS A 1553 BUS BUS B Figure 3d. CPU/BCRTM Interface -- DMA Configuration BCRTM-22 5.4 RAM Interface The BCRTM’s RRD, RWR, and MEMCSO signals serve as read and write controls during BCRTM memory accesses. The host subsystem signals RD, WR, and MEMCSI propagate through the BCRTM to become RRD, RWR, and MEMCSO outputs to support a pseudo-dual-port. During BCRTM-RAM data transfers, the host subsystem’s memory signals are ignored until the BCRTM access is complete. - STARTING ADDRESS INITIALIZED BY CPU IN THE RT DESCRIPTOR SPACE REGISTER RECEIVE SUBADDRESS #1 RECEIVE SUBADDRESS #2 RECEIVE SUBADDRESS #31 TRANSMIT SUBADDRESS #1 TRANSMIT SUBADDRESS #2 UNUSED 5.5 Legalization Bus The BCRTM’s Manchester II encoder/decoder interfaces directly with the1553 bus transceiver, using the TAO-TAZ and RAZ-RAO signals for Channel A, and TBO-TBZ and RBZ-RBO signals for Channel B. The BCRTM 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.. TRANSMIT UNUSED MODE CODE #’S 0 & 16 MODE CODE #’S 1 & 17 BCRTM TIMRONB CHANNEL A SUBADDRESS #31 CHANNEL B CHA/B MODE CODE #’S 15 & 31 Figure 5. Descriptor Space CHANNEL A TXINHA CHANNEL B DUAL TRANSCEIVER TXINHB ILLEGAL BROADCAST SUBADDRESS Figure 4. Dual-Channel Transceiver ILLEGAL SUBADDRESS INTERRUPT WHEN ADDRESSED 6.0 REMOTE TERMINAL ARCHITECTURE The Remote Terminal architecture is a descriptorbased configuration of relevant parameters. It is composed of an RT Descriptor Space (see figure 5) and internal, hostprogrammable registers. The Descriptor Space contains only descriptors. Descriptors contain programmable subaddress parameters relating to handling message transfers. Each descriptor consists of four words: (1) a Control Word, (2) a Message Status List Pointer, (3) a Data List Pointer, and (4) an unused fourth word (see figure 6.) These words indicate how to perform the data transfers associated with the designated subaddress. INTERRUPT WHEN INDEX = 0 15 UNUSED 10 9 8 7 I I I I 6 0 INDEX MESSAGE STATUS LIST POINTER DATA LIST POINTER FOR FUTURE EXPANSION Figure 6. Remote Terminal Subaddress Descriptor BCRTM-23 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 BCRTM 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 this page). Message Status information -- including word count, an internally generated time tag, and broadcast and message validity information -- is provided for each message. The Message Status Words are stored in a separate Message Status Word list according to subaddress. The list’s starting locations are programmable within the descriptor. Message data, received or transmitted, is also stored in lists. The message capacity of the lists and the lists’ locations are user selectable within the descriptor. 6.1 RT Functional Operation The RT off-loads the host computer of all routine data transfers involved with message transfers over the 1553B bus by providing a wide range of user-programmable functions. These functions make the BCRTM’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 (see figure 6). The BCRTM then reads the descriptor words when servicing a command corresponding to the specified descriptor. All bitselectable functions are active high and inhibited when low. 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 BCRTM 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 BCRTM 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 BCRTM 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 BCRTM 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 BCRTM 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 BCRTM 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 written and the pointer is incremented when the BCRTM detects a message error. C. Data List Pointer. The Data List Pointer is the third word within the descriptor. The BCRTM stores data in RAM beginning at the address indicated by the Data List Pointer. The Data List Pointer is updated at the end of each successful message with the next message’s starting address with the following exceptions: • If the message is erroneous, the Data List Pointer is not updated. The next message overwrites any data corresponding to the erroneous message. • Upon receiving a message, if the index is already equal to zero, the Data List Pointer is not incremented and data from the previous message is overwritten. D. Reserved. The fourth descriptor word is reserved for future use. BCRTM-24 6.1.2 Message Status Word Each message the BCRTM 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 7 WORD COUNT 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 #1 MESSAGE #1 #2 #3 MESSAGE #2 #4 MESSAGE STATUS LIST POINTER MESSAGE #5 #3 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 BIT 14 BIT 13 BITs 12-8 BITs 7-0 Subsystem Failed. Indicates SSYSF was asserted before the Message Status Word transfer to memory. This bit is also set when the user sets bit 13 of Register 10. Broadcast Message. Indicates that the corresponding message was received in the broadcast mode. Message Error. Indicates a message is invalid due to improper synchronization, bit count, word count, or Manchester error. 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 it should be, the Message Error bit in the 1553 status word is set. Time Tag. The BCRTM writes the internally generated Time Tag to this location after message completion. The resolution is 64µs. (See Register 13). If the timer reads 2, it indicates the message was completed 128 to 191µs after the timer started. BCRTM-25 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 can be 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 BIT 14 BIT 13 BIT 12 BIT 11 BIT 10 BIT 9 BIT 8 BIT 7 BITs 6-0 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. 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 MODECODE (WITHOUT DATA WORD) ILLEGALIZE MODE CODE (WITHOUT DATA WORD) RESERVED ILLEGALIZE BROADCAST MODECODE (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 6 0 INDEX MESSAGE STATUS LIST POINTER DATA LIST POINTER RESERVED Figure 9b. (RT) Mode Code Descriptor BCRTM-26 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). when the test is completed. A failure in BIT will also set the TF status word bit. The BCRTM can autonomously support 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 by setting the appropriate bit in the control word upon successful completion of the mode command by setting the appropriate bit in the control word (see figure 9b). Inhibit Terminal Flag Bit #00110 The BCRTM inhibits the Terminal Flag from being set in the status word. 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 BCRTM Status Register confirms the mode code acceptance. A HighPriority Interrupt is also asserted if enabled. If the Dynamic Bus Control Enable bit is not set, the BCRTM does not accept Dynamic Bus Control. Synchronize (Without Data Word) #00001 If enabled in the Mode Code #00001 Descriptor Control Word, the BCRTM asserts an interrupt when this mode code is received. Transmit Status Word #00010 The BCRTM automatically transmits the 1553 status word corresponding to the last message transacted. Initiate Self-Test #00011 The BCRTM 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 Transmitter Shutdown #00100 The BCRTM disables the channel opposite the channel on which the command was received. Override Transmitter Shutdown #00101 The BCRTM enables the channel previously disabled. Override Inhibit Terminal Flag Bit #00111 The BCRTM disables the Terminal Flag inhibit. Reset Remote Terminal #01000 The BCRTM automatically resets the encoder, decoders, and protocol logic. Transmit Vector Word #10000 The BCRTM 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 BCRTM simply stores the associated data word. Transmit Last Command #10010 The BCRTM transmits the last command executed and the corresponding 1553 status word. Transmit BIT Word #10011 The BCRTM transmits BIT information from the BIT Register. Selected Transmitter Shutdown #10100 On receiving this mode code, the BCRTM simply stores the associated data word. Override Selected Transmitter Shutdown #10101 On receiving this mode code, the BCRTM simply stores the associated data word. BCRTM-27 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 µs for RT-RT transfers. If the response time-out condition occurs, a Message Error bit can be 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. generated internally.Writing to Register 10 enables the other predefined bits. For illegalized commands, the BCRTM also sets the Message Error Bit in the 1553 Status Word. 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 BCRTM is put in a hold state until the interrupt is acknowledged (by writing a “1” to the appropriate bit in Register 8). 6.3 RT Operational Sequence The following is a general description of the typical behavior of the BCRTM 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. For Standard Interrupts: DMA arbitration (BURST) Interrupt Status Word write RT Descriptor Block Pointer write Tail Pointer read (into Register 6) STDINTP pulses low STDINTL asserted (if enabled) Processing continues Valid Command Received. COMSTR goes active • DMA Descriptor Read. After receiving a valid command, the BCRTM 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 BCRTM 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 BCRTM receives data, it writes each Data Word to memory after the Data Word is received: DMA arbitration Data Word write (starting at Data List Pointer address, incremented for each successive word) Status Word Transmission. The BCRTM automatically transmits the Status Word as defined in MIL-STD-1553B.The Message Error and Broadcast Command Received bits are BCRTM-28 • Descriptor Write. After the BCRTM 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. 7.0 BUS CONTROLLER ARCHITECTURE The BCRTM’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 11 and 12). 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 HEAD POINTER 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. CONTROL WORD COMMAND WORD 1 The Bus Controller also has a programmable intermessage delay timer that facilitates message transfer scheduling (see figures 13 and 14). This timer, programmed in the control word, automatically delays between the start of two successive commands. COMMAND WORD 2 (RT-RT ONLY) DATA LIST POINTER STATUS WORD 1 STATUS WORD 2 (RT-RT ONLY) 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. 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. COMMAND BLOCK #1 HP TP #2 COMMAND BLOCK HP DATA WORD #1 DATA LIST POINTER DATA WORD #2 X TP #3 LAST DATA WORD HP X IS BETWEEN 1 & 32 Figure 11. Data Placement TP 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 BCRTM’s register set provides additional global parameters and address pointers. HP #4 TP Figure 12. Command Block Chaining BCRTM-29 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 BCRTM’s operation. The host determines the first Command Block by setting the initial starting address in the current Command Block Register. Once set, the BCRTM updates the current Command Block Register with the next Command Block 15 MESSAGE ERROR 14 SKIP 13 12 11 INTERRUPT AND CONTINUE POLLING ENABLE AUTO RETRY ENABLE Address. The BCRTM then executes the sequential 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 section 9.0, Exception Handling and Interrupt Logging). The functions and their programming instructions are described below. The registers also contain many programmable functions and function parameters. 10 9 END OF LIST 8 RT-RT TRANSFER MONITOR RT-RT TRANSFER 7 0 ‘TIME DELAY’ Figure 13. Command Word MESSAGE #1 MESSAGE #2 TDELAY1 MESSAGE #3 TDELAY2 Figure 14. BC Timing Delays 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 BCRTM does not access this location. B. Control Word. Host-written, the Control Word contains bit-selectable options and a Message Error bit the BCRTM provides (see figure 13). The bit definitions follow. Bit Number BIT 15 BIT 14 BIT 13 BIT 12 BIT 11 BIT 10 BIT 9 BCRTM-30 Description Message Error. The BCRTM sets this bit when it detects an invalid RT response as defined in MIL-STD 1553B. Skip. When set, this bit instructs the BCRTM to skip this Command Block and execute the next. 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. Polling Enable. Enables the BCRTM’s polling operation. Auto Retry Enable. When set, the Auto Retry function, governed by the global parameters in the Control Register, is enabled for this message. End of List. Set by the CPU, this bit indicates that the BCRTM, 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. 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 BCRTM should receive and store the message beginning at the location indicated by the data pointer. Time Delay. The CPU sets this field, which causes the BCRTM 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 BCRTM will at least meet the minimum 4µs 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: BITs 7-0 • Timer resolution is 16µs. As an example, if a given message requires 116µs to complete (including the minimum 4ms 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 the 4ms 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 time 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 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 BCRTM, this location contains the entire Remote Terminal status response. G. Status Word Two. Stored by the BCRTM, 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. Compare Register contents. Program the PCR by setting the PCR bits corresponding to the RT’s 1553 status word bits RAM COMMAND BLOCK #1 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 DATA WORD #1 Control Word and in the Standard Interrupt Enable Register DATA POINTER (Register 9), a polling comparison interrupt is generated. MESSAGE #1 DATA WORD #2 DATA WORD #3 DATA WORD #1 COMMAND BLOCK #2 DATA WORD #2 MESSAGE #2 DATA WORD #3 DATA POINTER Example 1. No bit match is present PCR 00000000001 RT’s 1553 Status Word response 00000100010 Result No Polling Comparison Interrupt DATA WORD #4 Example 2. Bit match is present PCR 00100100000 RT’s 1553 Status Word response 00000100000 Result Polling Comparison Interrupt 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 BCRTM 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 7.3 BC Error Detection The Bus Controller checks for errors (see the Exception Handling and Interrupt Logging and the RT Error Detection sectons, pages 37 and 28) 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-1553. Illogical commands include incorrectly formatted RT-RT Command Blocks. BCRTM-31 B. For RT-to-BC Command Blocks: The BCRTM transmits the Command Word. RT RT RT • Status Word DMA The BCRTM receives the RT Status Word. RESPONSE Q? BC DMA arbitration Status Word write (to sixth location of Command Block) The BCRTM receives the first Data Word. • Data Word DMA 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 BCRTM as it processes a message in the BC mode. The user starts BC operation by writing a “1” to Register 0, Bit 0. • Command Block DMA - the following occurs immediately after Bus Controller startup: DMA arbitration (BURST) Control Word read Command Word 1 read (from third location of Command Block) Data List Pointer read A. For BC-to-RT Command Blocks: The BCRTM transmits the Command Word. • Data Word DMA DMA arbitration Data Word read (starting at Data List Pointer address, incremented for each successive word) The BCRTM transmits the Data Word. Data Word DMAs and transmissions continue until all Data Words are transmitted. • Status Word DMA The BCRTM receives the RT Status Word. DMA arbitration Status Word write (to sixth location of Command Block) BCRTM-32 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(A)-to-RT(B) Command Blocks: The BCRTM transmits Command Word 1 to RT(B). • Command Word 2 DMA DMA arbitration Command Word 2 read (from fourth location of Command Block) The BCRTM transmits Command Word 2 to RT(A). The BCRTM receives the RT Status Word from RT(A). • Status Word DMA for RT(A) Status Word DMA arbitration Status Word write (to sixth location of Command Block) The BCRTM receives the first Data Word • Data Word DMA (only if the BCRTM 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 BCRTM receives the RT Status Word from RT(B). • Status Word DMA for RT(B) Status Word DMA arbitration Status Word write (to seventh location of Command Block) Block) Data List Pointer read Exception Handling. If an interrupting condition occurs during the message, the following occurs: The BCRTM proceeds again from point A, B, or C as shown above. For High-Priority Interrupts: HPINT is asserted (if enabled in Register 7). For message errors, the BCRTM is put in a hold state until the interrupt is acknowledged (by writing a “1” to the appropriate bit in Register 8). For Standard Interrupts: DMA arbitration (BURST) Interrupt Status Word write Command Block Pointer write Tail Pointer read (into Register 6) STDINTP pulses low STDINTL asserted (if enabled) Processing continues 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 BCRTM proceeds from the current Command Block to the next successive Command Block. • If no Message Error has occurred during the current Command Block, the following occurs: 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 • If the BCRTM 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 7.5 BC Operational Example (figure 22) The BCRTM is programmed initially to accomplish the following: The first Command Block is for a four-word RT-RT transfer with the BCRTM monitoring the transfer and storing the data. • Auto-retry is enabled on the opposite bus using only one retry attempt, if the incoming Status Word is received with the Message Error bit set. • Wait for a time delay of 400 microseconds before proceeding to the next Command Block. • The Data List Pointer contains the address 0400H. 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 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 BCRTM, 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 BCRTM then waits to receive the Status Word back from the transmitting RT. C. The BCRTM 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 BCRTM 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. BCRTM-33 D. The BCRTM receives the Status Word response from the receiving RT. The ME bit in the Status Word is set, indicating the message is invalid. The BCRTM 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 135µs before proceeding. This is determined as follows: The message transaction time is approximately130µs (the only approximation is due to the range in status response and intermessage gap times specified by MILSTD-1553B). Approximating that with the retry, the total duration for the two attempts is 265µs. F. The BCRTM 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 BCRTM transmits the receive command followed by two data words from locations 0404H - 0405H in memory. The BCRTM reads the second data word from memory while transmitting the first. 8.0 BUS MONITOR ARCHITECTURE The BCRTM’s bus monitor architecture is based on a Command Block structure and internal, host-programmable registers. Each message transactedover the MIL-STD1553B bus (for a monitored RT address) has an associated Command Block, which the CPU sets up (see figures 17 and 18). 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. MONITOR CINROL/STATUS 1553 COMMAND WORD 1 1553 COMMAND WORD DATA LIST POINTER 1553 STATUS WORD 1 1553 STATUS WORD 2 TAIL POINTER Figure 17 BCRTM Bus Monitor Command Block In a linked list Command Block structure, pointers delimit each Command Block to the successive block (see figure 19) A data pointer9 in theCommand Block allows efficient space allocation because data blocks do not have to be placed contiguosly in memory COMMAND BLOCK #1 DATA WORD #1 H. The BCRTM 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. J. The Status Word is stored in the Command Block. The BCRTM, having encountered the end of the list, halts message transactions and waits for another start signal. The BCRTM asserts a High-Priority Interrupt indicating the end of the command list. Due to the polling comparison match, the BCRTM also asserts a Standard Priority Interrupt and logs the event in the Interrupt Log List. BCRTM-34 DATA LIST POINTER DATA WORD #2 X LAST DATA WORD X IS BETWEEN 1 & 32 Figure 18. Data Placement A Monitor control/status word with an eight-bit Time Tag, an Interrupt When Addressed bit, a Message Error bit, and a Command Block Activated bit are in each Monitor Command Block. The user can access these control/status words to determine which Monitor Command Block, the host can determine when particular remote terminal has occured. 8.1 Monitor Functional Operation The Bus Monitor function is a register-selectable mode of operation. The host users registers 14, 16, and 17 in conjunction with Register 0 to program the BCRTM to monitor any combination of remote terminals or all of the remote terminals. COMMAND BLOCK #1 CONTROL WORD TP #2 the BCRTM’s memory mangement scheme gives the host a great deal of flexibility for processing 1553 bus data and is compatible with may bus monitoring applications. the host CPU is responsible for processing initializing the Monitor Control Blocks. The Monitor structure is analogous to the Bus Controller Command Block scheme. the only real difference is the direction of information flow. CONTROL WORD The number of Monitor Control Blocks that the host initializes depends on the data latency requirements for post-processing of 1553 commands. the linked list of Command Blocks could be connected in a loop fashion, with the BCRTM accessing the loop at one point and the host CPU processing the message behind that point. The bit positions of the BM control/status word are defined as shown in figure 20. TP 15 CBA 14 ME TP #3 CONTROL WORD #4 CONTROL WORD TP Figure 19. Monitor Command Block Tail Pointers 13 12 11 10 IOA BA/B X X 9 X 8 X 7 6 5 4 3 2 1 0 TT7 TT6 TT5 TT4 TT3 TT2 TT1 TT0 B0 - B7 B8 - B11 B12 - Bus A/B: B13 - IWA: B14 - ME: B15 - CBA: Time Tag (64µs resolution) Not Used Defines which of the dual redundant 1553 buses on which the BCRTM received this message Interrupt When Addressed. The BCRTM issues a standard priority interrupt when the monitor accesses this Bus Monitor Command block. Message Error. The BCRTM sets this bit if a 1553 message error occurred while receiving this message. Command Block Activated. The BCRTM sets this bit when this Bus Monitor Command Block is accessed by the BCRTM. Figure 20: Bus Monitor Control/Status Word 8.2 Monitor Error Detection in the Monitor mode, the BCRTM chaecks all monitored messages for errors. Detectable errors include word count errors, long words, short words, Manchester errors (including zero crossing deviation), parity errors, and data contiguity. Bus Controller, since the status syncis identified to the command sync. In this case, the BCRTM will put the extra status word in a new Monitor Command Block, and then report a Message Error due to the to the incorrect protocol on the erroneously interpreted status word the RT transmitted. Due to the nature of the 1553 protocol, it ca be very difficult for any monitoring device to interpret some types of errors on the 1553 bus. For example, suppose an RT (whose RT Address the BCRTM is monitoring) incorrectly responds to a Broadcast command. The BCRTM, which is not receiving or transmitting the message, cannot distinguish between the erroneous status word and a new command sent from the 8.3 Monitor Operational Sequence The following is a general description of the operation of the BCRTM as it processes a monitored BC-to-RT message in the Monitor mode. DMA operations will vary slightly depending on the type of message (i.e., RT-to-BC, RT-toRT, etc.) It is assumed that the user has already written a "1" to BCRTM-35 Upon completion of the message, the BCRTM initiates a DMA cycle to update the status word and fetch the address of the next Monitor Command block: Register 0, bit 0, and all other registers are in the appropriate state to enable Monitor operation. Valid Command Received. DMA arbitration (BURST) Control/ Status Word write Tail Pointer write COMSTR goes active • DMA Command Block Read. After receiving a valid command, the BCRTM initiates a burst DMA: DMA arbitration (BURST) Control Word read Command Word Write Data List Pointer read Data Received. • The exception handling scheme the BCRTM uses is based on an interrupt structure and provides a high degree of flexibility in: • defining the events that cause an interrupt, Data Word DMA. • The BCRTM initiates a DMA cycle for each Data Word to store the data in memory, whether the command was a transmit or receive command to any valid monitored RT Address. selecting between High-Priority and Standard interrupts, and • selecting the amount of interrupt history retained. DMA arbitration Data Word write (starting at Data List Pointer address, incremented for each successive word) Status Word Received. • 9.0 E XCEPTION HANDLING AND INTERRUPT LOGGING Status Word DMA. DMA arbitration Status Word write. 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 BCRTM is put in a hold state until the interrupt is acknowledged (by writing a “1” to the appropriate bit in Register 8). For Standard Interrupts: DMA arbitration (BURST) Interrupt Status Word write Command Block Pointer write Tail Pointer read (into Register 6) STDINTP pulses low STDINTL asserted (if enabled) Processing continues Message Completion BCRTM-36 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 23, and the Bus Controller Command Block definition, page 31), and an Interrupt Log List that sequentially stores an interrupt events record in system memory. The BCRTM generates the Interrupt Log List (see figure 21) 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 BCRTM 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. 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 noncontagious blocks of memory. The host CPU sets the list’s starting address using the Interrupt Log List Register. The BCRTM 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 also uses three BCRTM- driven output signals to indicate when an interrupt event occurs: STDINTL INTERRUPT LOG LIST POINTER REGISTER Standard Interrupt Level. This signal is asserted when one or more of 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. ENTRY #1 INTERRUPT STATUS WORD COMMAND BLOCK POINTER SUBADDRESS/MODE CODE DESCRIPTOR POINTER TAIL POINTER STDINTP Standard Interrupt Pulse. This signal is pulsed for each occurrence of an event enabled in the Standard Interrupt Enable Register. ENTRY #2 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. ENTRY #3 Figure 21. Interrupt Log List 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. BCRTM-37 BCRTM-38 BCRTM ACTIVITY DESCRIPTION READ LOG LIST TAIL PTR STORE CMD BLOCKPTR STORE INTERRUPT STATUS WORD RECOGNIZE ME BIT STORE STATUS WORD #2 * STATUS RTI 2 DATA 4 RTI 2 DATA 3 RTI 2 DATA 2 RTI 2 DATA 1 RTI 2 AUTO RETRY * FETCH DATA WORD #2 FETCH DATA WORD#1 FETCH DATA POINTER FETCH COMMAND WORD FETCH CONTROL WORD TIME OUT TO 400 µs Figure 22. Bus Controller Scenario 400µs STATUS RTI 1 344 to 392µs Notes: 1. Times for DMA Arbitration and BCRTM 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 CONTROL WORD BCRTM DMA ACTIVITY STATUS FETCH DATA POINTER FETCH COMMAND WORD #1 INTERRUPT FETCH DATA POINTER FETCH COMMAND WORD #1 FETCH CONTROL WORD START BCRTM INITIALIZE REGISTERS RTI BC CMD #1 CMD #2 BC FETCH COMMAND WORD #2 BCRTM DMA ARBITRATION3 FETCH COMMAND WORD #2 MANCHESTER DATA BUS B * STORE STATUS WORD #1 DATA 2 BC STORE DATA WORD#1 484 to 492µs STORE DATA WORD #2 DATA 1 BC RTI 1 * STATUS DATA 4 RTI 2 STORE DATA WORD#3 DATA 3 RTI 2 STORE DATA WORD#4 DATA 2 RTI 2 STORE STATUS WORD #1 CMD RTI 2 STATUS DATA 1 RTI 2 STORE DATA WORD#1 BC * 175 to STORE DATA WORD#2 400µs BC CMD #1 CMD #2 BC 168 to STORE DATA WORD #3 MANCHESTER DATA BUS A BCRTM ACTIVITY DESCRIPTION BCRTM DMA ACTIVITY INTERRUPT BCRTM DMA ARBITRATION3 MANCHESTER DATA BUS B MANCHESTER DATA BUS A 0µs TIME OUT TO 400 µS FETCH TAIL POINTER STORE STATUS WORD #2 STORE DATA WORD#4 EOL IN CONTROL WORD SO STOP BCRTM STORE INTERRUPT STATUS WORD BIT TIMES 1 2 3 4 5 6 7 5 COMMAND WORD SYNC REMOTE TERMINAL ADDRESS 8 9 10 11 1 12 13 14 15 16 5 SUBADDRESS/ MODE T/R 17 18 19 5 20 1 DATA WORD COUNT/MODE CODE P DATA WORD SYNC DATA P PARITY TERMINAL FLAG DYNAMIC BUS CONTROL ACCEPTANCE SUBSYSTEM FLAG BUSY RESERVED BROADCAST COMMANDRECEIVED SERVICE REQUEST Note: T/R - transmit/receive P - parity REMOTE TERMINAL ADDRESS INSTRUMENTATION SYNC MESSAGE ERROR STATUS WORD Figure 23. MIL-STD-1553B Word Formats BCRTM-39 10.0 ABOSOLUTE MAXIMUM RATINGS* (REFERENCED TO VSS) SYMBOL PARAMETER LIMITS UNIT VDD DC supply voltage -0.3 to + 7.0 V VI/O Voltage on any pin -0.3 to VDD + 0.3 V VI DC input current ± 10 mA TSTG Storage temperature -65 to + 150 °C TJMAX Maximum junction temperature + 175 °C PD Average power dissipation 1 300 mW Thermal resistance, junction-to-case 12 ° C/Watt ΘJC Notes: 1. Does not reflect the added PD due to an output short-circuited. * Stresses outside the listed absolute 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 thisspecification is not recommended. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. RECOMMENDED OPERATING CONDITIONS SYMBOL PARAMETER LIMITS UNIT VDD DC supply voltage 4.5 to 5.5 V TC Temperature range -55 to +125 °C FO Operating frequency 12 ±.01% BCRTM-40 MHz 11.0 DC ELECTRICAL CHARACTERISTICS (VDD = 5.0V ± 10%; -55°C < TC < + 125°C) SYMBOL PARAMETER CONDITION MINIMUM MAXIMUM UNIT VIL Rad and Non-Rad Low-level input voltage TTL inputs VIH Non-Rad High-level input voltage TTL inputs VIH Rad-Hard High-level input voltage TTL inputs 7 IIN Non-Rad Input leakage current TTL inputs Inputs with pull-up resistors Inputs with pull-up resistors VIN = VDD or VSS VIN = VDD VIN = VSS -1 -1 -550 -1 -1 -80 µA µA µA IIN Rad-Hard Input leakage current TTL 7 Inputs with pull-up resistors Inputs with pull-up resistors VIN = VDD or VSS VIN = VDD VIN = VSS -10 -10 -900 10 10 -150 µA µA µA VOL 1 Low-level output voltage TTL outputs I OL = 3.2mA 0.4 V 1 High-level output voltage TTL outputs I OH = -400µA 2.4 VO = VDD or VSS -10 VDD = 5.5V, VO = VDD VDD = 5.5V, VO = 0V -110 VOH IOZ 0.8 Three-state output leakage current TTL outputs Short-circuit output current CIN Input capacitance CIO IDD QIDD 3 Bidirect I/O capacitance 3 Average operating current Quiescent current8 1, 2 3 Output capacitance 2.0 V 2.2 V 6 IOS COUT V 1, 4 V 10 µA 110 mA mA ƒ = 1MHz @ 0V 10 pF ƒ = 1MHz @ 0V 15 pF ƒ = 1MHz @ 0V 20 pF 50 mA 1 35 mA µA ƒ = 12MHz, CL = 50pF +125o C See Note 5, Tc = Tc = 25oC, -55oC Notes: 1. Supplied as a design limit, but not guaranteed or tested. 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. 6. Functional tests are conducted in accordance with MIL-STD-883 with the following input test conditions VIH = VIH(min) +20%, -0%; VIL = VIL(max) +0%, -50%, as specified herein, for TTL-compatible inputs. Devices may be tested using input voltage within the above specified range, but are guaranteed to VIH(min) and VIL(max). 7. To 1.0E6 total dose; above this level, CMOS I/Os required. 8. Guaranteed to pre- and post-irradiation limits. BCRTM-41 12.0 AC ELECTRICAL CHARACTERISTICS (OVER RECOMMENDED OPERATING CONDITIONS) VIH 1 INPUT VIL MAX tb ta IN-PHASE OUTPUT OUT-OF-PHASE OUTPUT VIH MIN VIL MAX 1 tc 2 2 2 td 2 VOH MIN VOL MAX VOH MIN VOL MAX te VOH MIN BUS VOL MAX tf tg th SYMBOL ta PARAMETER INPUT↑ to response↑ INPUT↓ to response↓ tb tc td INPUT↑ to response↓ INPUT↓ to response↑ INPUT↓ to data valid INPUT↓ to high Z INPUT↑ to high Z INPUT↑ to data valid te tf tg th Notes: 1. Timing measurements made at (VIH MIN + VIL MAX)/2. 2. Timing measurements made at (VOL MAX + VOH MIN)/2. 3. Based on 50pF load. 4. Unless otherwise noted, all AC electrical characteristics are guaranteed by design or characterization. Figure 24. Typical Timing Measurements 5V IREF (source) 90% 3V 90% VREF • 50pF 10% 10% 0V IREF (sink) Output Loading < 2ns < 2ns Input Pulses Note: 50pF including scope probe and test socket Figure 25. AC Test Loads and Input Waveforms BCRTM-42 DMA GRANT RECOGNIZED ON THIS EDGE MCLKD2 tSHL1 DMAR DMAG tPW2 DMACK TSCTL MEMCSO ADDRESS DATA RWR/RRD 2 AEN BURST tPHL1 tOOZL1 tPZL1 tPHL2 tHLH2 tPHL3 tPHL4 SYMBOL tSHL16 tPHL1 tPHL21 tPZL16 tHLH2 tPHL3 tPW21 tOOZL1 tPHL4 tPHL4 Notes: PARAMETER DMACK↓ to DMAR High Impedance RAD NON-RAD 3 DMAG↓ to DMACK↓ DMAG↓ to TSCTL↓ TSCTL↓ to ADDRESS valid RAD NON-RAD RWR/RRD↑ to DMACK↑ TSCTL↓ to RWR/RRD↓ DMAG↓ to DMAG↑ DMAR↓ to BURST↑ DMAR↓ to DMAG↓ 5 DMAR↓ to DMAG↓ 4 MIN -2 0 40 40 UNITS ns ns ns ns ns ns THMC1-10 MCLK-20 MCLK THMC1+10 MCLK+20 6xMCLK ns ns ns -10 0 0 10 3.5 (1.9) 1.9 (0.8) ns µs µs -5 10 0 2x-2MCLK MAX +5 10 45 4xMCLK 1. Guaranteed by test. 2. See figures 27 & 28 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 27). Figure 26. BURST DMA Timing BCRTM-43 tIOHL1 tPLH1 THMC1 THMC2 MCLK MCLKD2 TSCTL MEMCSO tPLH2 tHLZ2 ADDRESS DATA RRD tHLZ1 tSHL1 t SLH1 SYMBOL tSHL1 tPW1 tHLZ tHLZ2 tSLHI MIN ADDRESS valid to RRD↓ (ADDRESS set-up) RAD ) NON-RAD 2 tPLH1 tPLH2 PARAMETER 1 tIOHL1 RRD↓ to RRD↑ RRD↑ to ADDRESS High Impedance RRD↑ to DATA High Impedance DATA valid to RRD↑ MCLK↑ to MCLKD2↑ MCLK↑ to TSCTL/MEMCSO↓ 1 MCLK↑ to RRD↓ (ADDRESS hold) (DATA hold) (DATA set-up) -5 10 +5 10 MCLK-10 MCLK+5 THMC1+10 THMC1+10 5 40 0 0 0 Note: 1. Guaranteed by test. 2. Pre- and Post-Irradiation Limits. Figure 27. BCRTM DMA Read Timing (One-Word Read) BCRTM-44 MAX 40 40 60 UNITS ns ns ns ns ns ns ns ns tIOHL1 tPLH1 THMC1 THMC2 MCLK MCLKD2 TSCTL MEMCSO tPLH2 tHLZ2 ADDRESS DATA RWR tSHL1 SYMBOL tSHL12 tOOZL11,2 tHLZ1 tHLZ2 tPW1 tPLH1 tPLH2 tIOHL1 1 1 PARAMETER ADDRESS valid to RWR↓ RWR↓ to DATA valid NON-RAD RAD tOOZL1 tHLZ1 tPW1 MIN MAX (ADDRESS setup) THMC2-10 THMC2+5 0 -5 30 30 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 2. Pre- and Post-Irradiation Limits. Figure 28. BCRTM DMA Write Timing (One-Word Write) BCRTM-45 tOOZH2 tOOZH1 tHLH1 ADDRESS DATA RD+CS tHLH2 tPW1 SYMBOL tOOZH22 tHLH2 tOOZH1 2 tHLH1 tPW1 tPW2 PARAMETER ADDRESS valid to DATA valid RD+CS↑ to DATA High Impedance RD+CS↓ to DATA Valid RD+CS↑ to ADDRESS High Impedance RD+CS↓ to RD+CS↑ RD+CS↑ to RD+CS↓ MIN (DATA hold) (DATA access) (ADDRESS hold) tPW21 Notes: 1. Guaranteed by functional test. 2. User must adhere to both tOOZH1 and tOOZH2 timing constraints to ensure valid data. 5 5 60 80 MAX 80 50 60 - UNITS ns ns ns ns ns ns Figure 29. BCRTM Register Read Timing tSHL1 tPW1 tHLH2 ADDRESS DATA WR+CS tHLH1 tPW2 tSHL2 SYMBOL tSHL1 tSHL2 tPW1 tHLH1 tHLH2 PARAMETER ADDRESS valid to WR+CS↓ DATA valid to WR+CS ↓ WR+CS↓ to WR+CS↑ (DATA hold) WR+CS↑ to DATA High Impedance WR+CS↑ to ADDRESS High Impedance (ADDRESS hold) WR+CS↑ to WR+CS↓ tPW21 Note: 1. Guaranteed by functional test. BCRTM-46 MIN (ADDRESS setup) (DATA setup) Figure 30. BCRTM Register Write Timing 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 tPLH2 1 tPHL3 1 PARAMETER RD↓ to RRD↓ WR↓ to RWR↓ MEMCSI↓ to MEMCSO↓ MIN MAX UNITS 0 30 ns 0 0 30 30 ns ns Figure 31. BCRTM Dual-Port Interface Timing Delays t PZLI MANCHESTER C D D DMA ACTIVITY SYMBOL tPZL11,2 PARAMETER Data word to DMA activity MIN 0 MAX UNITS µs 4 This diagram indicates the relationship between the incoming Manchester code and DMA activity (i.e., DMAR↓ to DMACK↑). Note: 1. The pulse width = (11µ s -tDMA -tPZL1) where tDMA is the time to complete DMA activity (i.e., DMAR↓ to DMACK↑). 2. Guaranteed by functional test. Figure 32. DMA Activity Memory Window (RT Mode) BCRTM-47 tPLH2 MCLK MCLKD2 DMAR DMAG DMAGO DMACK tSHL1 tPHL1 SYMBOL tPHL11 tSHL12 tPLH2 PARAMETER DMAG↓ to DMAGO ↓ DMACK↓ to DMAR High Impedance RAD NON-RAD MCLK↑ to MCLKD2↑ MIN MAX UNITS 0 30 5 10 ns -5 0 0 40 ns Notes: 1. When DMAG is asserted before DMAR, the DMAG signal passes through the BCRTM as DMAGO. 2. Pre- and Post-Irradiation Limits. Figure 33. BCRTM Arbitration when DMAG is Asserted before Arbitration BCRTM-48 ns 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/M Bus Controller/Remote Terminal/Monitor: SMD 5962 * * * * * Lead Finish: (A) = Solder (C) = Gold (X) = Optional Case Outline: (X) = 84 pin PGA (NonRad only) (Y) = 84 pin FP (Z) = 84 pin LCC (NonRad only) Class Designator: (-) = Blank or No field is QML Q (V) = Class V Drawing Number: 8957701 Total Dose: (F) = 3E5 (300KRad) (G) = 5E5 (500KRad) (H) = 1E6 (1MRad) (R) = 1E5 (100KRad) (-) = 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. 5962-89577Q1YX). 4. 84 LCC only available with solder lead finish. UT1553B BCRT/M Bus Controller/Remote Terminal/Monitor UT1553B/ BCRTM- * * * * 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 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.