MITEQ TECHNICAL NOTE 25T022 MARCH 2000 REV H LOCAL/REMOTE CONTROL and FUNCTIONAL DESCRIPTION UNIVERSAL Ku-BAND TEST TRANSLATOR UNIVERSAL DBS BAND TEST TRANSLATOR GENERAL DESCRIPTION The Universal Band Test Loop Translator (TLT) is a wideband single conversion translator. It is designed for applications where various transmit-to-receive translations are required. The translator is microprocessor controlled and soft-key menu driven for rapid set up and easy operation. Translator parameters are selected by choosing a satellite name or a combination of uplink, downlink and translation frequencies. The translator features a large back lit display, function keys and a scroll knob to provide instant access to operating parameters. All operating parameters are accessible locally or via the remote interface bus. Software upgrades and revisions to a library of satellites can be achieved through the use of PCMCIA memory card. FEATURES OPTIONS Local or remote control Minimum amplitude and delay distortion High frequency stability Low intermodulation distortion 30 db input level control Low phase noise contribution Summary alarm Complete control and monitoring capability over a remote bus (RS232, RS422, or IEEE-488). RS485 is standard. 60 db total input level control Higher frequency stability External 5 MHz reference 1
FRONT PANEL OPERATIONS The front panel display and indicators have been organized so that important information is available at a glance. The keyboard is divided into functional groups which allow an operator to easily change any parameter from the front panel. See Figure 1 for the physical layout of the front panel. KEYPAD OPERATION Figure 1. Front Panel, Universal Band Translator The keypad is divided into five functional groups (Power, Screen Select keys, Soft-keys, Data Entry and Local/Remote Select). The error tone will sound when an illegal key is pressed and in some cases, a warning message will be displayed. POWER The AC Power switch is located on the lower right of the front panel. To cycle power simply push this button. The push-button LED is lit when power is on. SCREEN SELECT KEYS The Screen Select keys are located to the right of the display area. They allow the operator to switch between the five screens with ease. By pressing one of the five screen select keys instant access to pertinent data is granted. The CNTRL key is operative in both Local and Remote modes. SOFT-KEYS The five Soft-keys, adjacent to the display, are labeled A through E. The context of these keys is screen dependent. A brief definition is presented, on the active screen, adjacent to the soft-keys. Pressing undefined soft-keys will cause an error tone to sound. DATA ENTRY The Data Entry keys, along with the scroll knob, allow the operator to enter specific data into an active field. Data is entered using the numbered keys or scroll knob then pressing the ENT key. Invalid entries will be ignored and cause an error tone to sound. While in Remote mode, local data entry is prohibited, however, all system parameters can be examined. 2
LOCAL/REMOTE SELECT The front panel REMOTE key selects either Local (LED off) or Remote mode (LED on). The mode alternates with each key press. On units equipped with the IEEE-488 remote option this key puts the unit into Local mode only as dictated by that standard. While in Local mode, translator settings can be changed using the front panel. All of the status information can be monitored over the remote bus. Remote attempts to alter the translator settings will be ignored. With translator settings under remote control, the system parameters can be observed locally. Efforts to alter the translator settings from the front panel, while in Remote mode, will be ignored and cause an error tone to sound. LCD DISPLAY The LCD display is TNT type with a cold cathode fluorescent tube backlight. The display automatically shuts off the back-light after 5 minutes of continuous operation without front panel input. ALARM STATUS If any alarms exist, a three second tone will sound every thirty seconds until the alarm is cleared. The LCD back-light will not automatically shut off after 5 minutes of non use while an alarm is present. The system power supply voltages out of range and the LO out-of-lock can cause an alarm. Alarm status can be examined in both Local and Remote modes on the System Monitor screen. SUMMARY ALARM A summary alarm condition exists while any alarm is present and will automatically be cleared when all components return to the normal condition. LOCAL OPERATION In Local mode, the translator is controlled from the front panel. System parameters can still be monitored over the remote bus, however, attempts to change settings remotely, while in Local mode, will be ignored. The five front panel Screen Select Keys are located to the right of the LCD display. These keys control the display and allow data entry into the various functional areas of the translator. The five soft-keys, labeled A through E, are context sensitive with respect to the current screen. There are five different screens, one for each Screen Select Key plus the default system monitor screen. The screens available are: System Monitor (default) Satellite Name Uplink Band Downlink Band Translation Frequency Control 3
SETTING THE TRANSLATOR CONFIGURATION FROM THE FRONT PANEL A TLT configuration is composed of three parameters. They are: input band, output band, and translation frequencies. The translator is equipped with a library of satellites which reside in nonvolatile memory. A specific configuration is associated with each satellite name in that library. The translator can be configured by simply selecting a satellite name from the library. Pressing a screen select key activates the appropriate screen. Once selected, a list of choices is displayed on the lower portion of the screen. The appropriate parameter for that screen is highlighted by reversed video on both the upper and lower portions of the screen and the title for that parameter on the upper portion of the screen starts flashing. Use the scroll knob to scroll through the list on the lower portion of the screen then press the ENT key to make the selection. The ENT key must be pressed within 60 seconds to select the highlighted entry and stop the flashing. Otherwise an error tone will sound and the screen will return to the current settings and default System Monitor Screen. The translator can also be configured be selecting each of the three individual elements; input band, output band, and translation frequency. The first parameter to be selected, will cause the satellite name and the remaining two parameters to clear. The uplink band, downlink band and translation frequency titles will all start flashing, indicating that all three parameters must be set before the translator can be set. As each parameter is set, its title stops flashing. When the last parameter is set, the translator will be set to the selected settings. If the unit is left idle for 60 seconds and at least one title is flashing, a time-out condition will arise causing the error tone to sound and the screen to return to the current settings and default System Monitor Screen. CUSTOM SATELLITE CONFIGURATIONS Up to eight (optionally more) custom configurations can be added to the library, each with a preassigned name CUSTOM0 through CUSTOM7. An alias name can also be assigned to each custom configuration by a remote command. The custom configurations can be recalled from memory using either its preassigned satellite name or its alias name. To add a custom satellite configuration to the list, select ADD A CUSTOM CONFIGURATION from the satellite name screen. A list of custom satellite names will be displayed on the bottom portion of the screen. Using the scroll knob, choose a name from the list and press the ENT key. Now set the uplink band, downlink band and translation frequency. When all four entries are complete; the satellite name, uplink band, downlink band and translation frequency, the custom configuration will be added to the top of the current satellite list and the translator will be configured to these settings. To edit a custom configuration in the list, select EDIT A CUSTOM CONFIGURATION from the satellite name screen. A list of custom satellite names will be displayed on the bottom portion of the screen. Using the scroll knob, choose a name from the list and press the ENT key. Now set the uplink band, downlink band and translation frequency. When all four entries are complete; the satellite name, uplink band, downlink band and translation frequency, the custom satellite configuration will be changed and the translator will be configured to these settings. 4
SYSTEM MONITOR SCREEN The System Monitor Screen displays the satellite name, uplink band, downlink band, translation frequency and input attenuation value. The system DC voltages, phase voltage and alarms are also displayed for monitoring purposes. This screen is the default screen. 5
SATELLITE NAME SCREEN The Satellite Name Screen displays the names of the satellites stored in the library. Pressing the SAT NAME screen select key activates this screen. The current selected satellite is displayed at the top of the screen along with the specific configuration currently selected. The satellite name at the top of the screen and in the satellite list is highlighted by reversed video. Selecting a satellite by name can be accomplished by scrolling through the list until the desired satellite is highlighted and then pressing the ENT key. The uplink band, downlink band, and translation frequency are updated as the list is traversed with the scroll knob to aid in the selection of a satellite (some satellites have multiple configurations). 6
UPLINK BAND SCREEN The Uplink Band Screen displays a list of the available uplink bands. Pressing the UPLINK screen select key activates this screen. The uplink band at the top of the screen and in the uplink band list is highlighted by reversed video. Select an uplink band by scrolling through the list until the desired uplink band is highlighted and then press the ENT key. If the downlink band and/or the translation frequency have been previously selected, the list of available uplink bands will be limited by those selections that match the list of satellites currently stored in the library. If the desired uplink band cannot be found in the list of available uplink bands, a band can be manually entered using the data entry keys. First enter the uplink band lower limit in GHz using the number keys and decimal point followed by the ENT key. Next enter the uplink band upper limit in GHz using the number keys and decimal point followed by the ENT key. An illegal range will cause the error tone to sound. Valid uplink bands are 12.75-13.75 GHz and 13.7-14.8 GHz for Ku Band and 17.3-18.1 GHz and 17.8-18.4 GHz for DBS Band. If the downlink band and/or translation frequency have not yet been selected, make these selections now by pressing either the DNLINK or XLATN Screen Select Key. 7
DOWNLINK BAND SCREEN The Downlink Band Screen displays a list of the available downlink bands. Pressing the DNLINK screen select key activates this screen. The downlink band at the top of the screen and in the downlink band list is highlighted by reversed video. Select a downlink band by scrolling through the list until the desired downlink band is highlighted and then press the ENT key. If the uplink band and/or the translation frequency have been previously selected, the list of available downlink bands will be limited by those selections to match the list of satellites currently stored in the library. If the desired downlink band cannot be found in the list of available downlink bands, a band can be manually entered using the data entry keys. First enter the downlink band lower limit in GHz using the number keys and decimal point followed by the ENT key. Next enter the downlink band upper limit in GHz using the number keys and decimal point followed by the ENT key. An illegal range will cause the error tone to sound. Valid downlink bands are 10.7-11.7 GHz, 11.2-12.2 GHz and 12.0-12.8 GHz for Ku Band and 10.7-11.7 GHz, 11.2-12.2 GHz and 11.7-12.7 GHz for DBS Band. If the uplink band and/or translation frequency have not yet been selected, make these selections now by pressing either the UPLINK or XLATN Screen Select Key. 8
TRANSLATION FREQUENCY SCREEN The Translation Frequency Screen displays a list of the available translation frequencies. Pressing the XLATN screen select key activates this screen. The translation frequency at the top of the screen and in the translation frequency list is highlighted by reversed video. Select a translation frequency by scrolling through the list until the desired translation frequency is highlighted and then press the ENT key. Choose the EXTERNAL entry in the list if an external LO is to be used as the translation frequency. If the uplink band and/or the downlink band have been previously selected, the list of available translation frequencies will be limited by those selections to match the list of satellites currently stored in library. If the desired translation frequency cannot be found in the list of available translation frequencies, a frequency can be manually entered using the data entry keys. Enter the translation frequency in GHz using the number keys and decimal point followed by the ENT key. An illegal frequency will cause the error tone to sound. Valid translation frequencies are 1.0-4.0 GHz for Ku Band and 4.0-8.0 GHz for DBS Band. If the uplink band and/or downlink band have not yet been selected, make these selections now by pressing either the UPLINK or DNLINK Screen Select Key. 9
CONTROL SCREEN The Control Screen provides access to various system parameters. Press the CNTRL screen select key to activate this screen. The soft-keys give simple access to the system parameters outlined below. The system attenuation level and the RF mute can both be accessed with the "A" soft-key. System attenuation level can be varied by controlling the applied attenuation. Press the A softkey until the attenuation parameter is highlighted by reversed video. Then use the data entry keys followed by ENT or the scroll knob to achieve the desired system gain. When a data entry key is pressed, the attenuation parameter starts flashing. The ENT key must be pressed within 60 seconds to select the entry and stop the flashing. Otherwise an error tone will sound and the parameter will return to the current setting. The RF mute can also be controlled by using the "A" soft-key. Press the "A" soft-key until the RF mute parameter is highlighted by reversed video. Use the scroll knob to toggle between enabled and disabled. Then press "ENT". The ENT key must be pressed within 60 seconds to select the entry and stop the flashing. Otherwise an error tone will sound and the parameter will return to the current setting. 10
The remote control parameters can be accessed by pressing the B through D soft-keys from the control screen. To modify particular parameters press the appropriate soft-key to activate that field. The selected parameter will be highlighted by reversed video. Scroll through the possible selections until the desired setting is displayed. When the scroll knob is turned, the title for that parameter starts flashing. Once the scroll knob is then left idle, the ENT key must be pressed within 60 seconds to select the entry and stop the flashing. Otherwise an error tone will sound and the parameter will return to the current setting. For the RS485, RS422 and RS232 serial interfaces the fields are: Soft-key B - Device Address (64-95) Soft-key C - Baud Rate 300 600 1200 2400 4800 9600 19200 Soft-key D - Parity Odd Even None For the IEEE-488 interface the fields are: Soft-key B - Device Address (00-30) Soft-key C - SRQ Enabled Disabled If necessary, the contrast and viewing angle of the LCD may be adjusted by pressing the E softkey then turning the scroll knob until the preferred setting is obtained. SOFTWARE REVISION The Software Revision level that is currently installed can be viewed on the Control Screen. This revision number is displayed as n.nn.t. Where n.nn is the revision of the Software and.t. is the revision of the Satellite Table. A revision of 1.01.F would indicate a Software revision of 1.01 and a Satellite Table revision of F. A new release could include a Software revision update, a Satellite Table revision or both. Refer to MITEQ Technote 25T016 for a typical Satellite Table. The Software and/or Satellite Table can be updated with a memory card available from MITEQ. 11
MODEL The Model Number of the software that is currently installed can be viewed on the Control Screen. SOFTWARE UPDATES The list of supported satellites and/or software enhancements can be brought up to date with a memory card. To update simply turn the translator off, insert the memory card into the slot and turn the translator back on. Press the A soft-key to update or the B soft-key to not update. If there is no user input for one minute, the system will automatically choose the B option which will skip the update and start the software that is currently loaded. When the update is complete, the unit will begin normal operation and the card should be removed. Custom configurations will not be changed by software updates. REMOTE OPERATION The translator is supplied with an RS485 bus interface or, as an option, can be supplied with RS232, RS422 or IEEE-488. The command structures for the first three buses, which are serial, are identical. The IEEE-488 format is similar with the exception that no header, trailer or checksum bytes are included in the structures. RS232/422/485 REMOTE PROTOCOL The command structures for the serial buses; RS232, RS422 and RS485 are identical. All transmissions are multi-byte sequences beginning with a header byte, and ending with a trailer byte and checksum byte. The transmitted bytes are all ASCII printable characters in the range of 20H to 7EH. Serial data format is a 10 bit sequence consisting of one start, 7 or 8 data, 1 or no parity, and 1 stop bit. All characters, including the checksum character, are checked for parity unless the NONE parity option is selected. If any character in a command message contains an error (parity, framing or overrun) or the checksum is incorrect, the command is ignored and no response is made. The remote parameters; Address, Baud Rate, and Parity are programmable from the front panel. The response time from command to acknowledge is 100 ms. maximum. All messages addressed to the translator are acknowledged with a response message. The translator continually monitors the communication bus and will accept commands addressed to it, even in Local mode. When in Local mode, receipt of any SET commands (commands beginning with $ ) will be ignored, and the translator will respond with an error code. 12
DEVICE ADDRESS/BAUD RATE/PARITY SELECTION The remote control parameters can be accessed by pressing the B, C and D soft-keys from the control screen. To change the device address press the B soft-key, scroll through the possible addresses (64-95) until the desired address is displayed, and press the ENT key or press the B soft key again to retain the former address. To set the baud rate press the C soft-key, scroll through (300-19200) until the desired baud rate is displayed, and press the ENT key or press the C soft key again to retain the former baud rate. To select the parity press the D soft-key, scroll through odd, even or none and press the ENT key or press the D soft key again to retain the former parity. MESSAGE FORMAT The message format is as follows: HEADER - TRANSLATOR ADDRESS - COMMAND/ERROR CODE - PARAMETERS - TRAILER - CHECKSUM The response time from command to acknowledge is 100 ms. maximum. HEADER BYTE The Header byte is 7BH, ASCII character "{". TRANSLATOR ADDRESS The translator may take on the address values from 64 to 95 (40H to 5FH). COMMAND CODE SUMMARY COMMAND CODES ASCII Character String NAM FRQ ATT ALR STA CUS MUT Function Satellite Name Satellite Frequencies Attenuation Alarm Status Status All Custom Satellite Alias Name RF Mute 13
ERROR CODE SUMMARY PARAMETERS ASCII Character Function a Command not recognized b Illegal parameter or out of range c Translator in Local mode d Translator busy Parameters are all ASCII printable characters in the range of 20H to 7EH. Numeric parameters are sent MSD first, LSD last. Values which do not adhere to the command format, or are beyond the allowable range, will be rejected and cause the translator to respond with an error code. TRAILER BYTE The Trailer byte is 7DH, ASCII character "}". CHECKSUM BYTE The checksum byte is the sum modulo 95 of all message characters beginning with the header byte up to and including the trailer byte. The value 32 is subtracted from each character value before taking the modulo 95 sum. The value 32 is added to the final sum to obtain the checksum value. All values are in decimal. Below is a program, written in the C programming language that illustrates the checksum calculation. Checksum = MOD [(character value - 32), 95] + 32 /* return the checksum character for the message in array subtract 32 from each character before taking modulo 95 sum add 32 to the final sum mes_len = message length */ char check_sum(char *array, char mes_len) { char i,sum; for (i = 0, sum = 0; i < mes_len; i++) { sum += *array++ - 32; sum %= 95; } return(sum + 32); } 14
COMMAND CODE DESCRIPTION The following paragraphs describe each of the command codes. For clarity the header, address, trailer and checksum characters are not shown. Upper case letters are the actual command or response characters. Lower case letters represent parameter character strings. Commands preceded by? are QUERY commands and those preceded by $ are SET commands. QUERY commands are used to examine system parameters remotely while SET commands are intended to modify system parameters. SATELLITE NAME = NAM The SET command has two forms. The first form specifies a satellite name only. The second form species a satellite name and frequency. A satellite name may appear more than once in the satellite tables. The only difference between these entries is the frequency associated with that name. When a satellite name appears in the list more than once, the first form of this command will select the first match found to that satellite name. The second form of this command can select any satellite in the list. Name Only Specified: The SET command requires that the name of the satellite be included as a parameter. Up to thirty characters are allowed for a satellite name. Names shorter than 30 characters are allowed. Embedded spaces are allowed. Trailing spaces are optional. Custom satellite names, custom satellite alias names as well as library satellite names can be used to select a satellite. Duplicate satellite names can exist in the satellite library and also in the custom satellite alias list. The search starts with the custom satellite list followed by the custom satellite alias list and finally the library satellite list. The first match found in this ordered search will be chosen. Name and Frequency Specified: The SET command requires a 30 character name and a frequency specification. The name must be 30 characters long. If the satellite name is less than 30 characters in length, trailing spaces must be appended to the name so that the total length of the name is 30 characters. Following the name is the ASCII string "FRQU" followed by two five digit parameters separated by an ASCII - for the uplink band, an ASCII D followed by two five digit parameters separated by an ASCII - for the downlink band, and an ASCII X followed by a seven digit parameter or the character string EXTERNAL for the translation frequency. Remote Command Sequence: $NAMnnnnn...nnnnn or $NAMnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnFRQUlllll-hhhhhDlllll-hhhhhXfffffff Response: $NAM nnnnn...nnnnn: 1-30 character name. nnnnnnnnnnnnnnnnnnnnnnnnnnnnnn: 30 character name. lllll: Five digit low band edge frequency expressed in MHz. hhhhh: Five digit high band edge frequency expressed in MHz. fffffff: Seven digit translation frequency expressed in khz or the character string EXTERNAL if the translation frequency is supplied externally. 15
The QUERY command requires no parameters. Remote Command Sequence:?NAM Response:?NAMnnnnnnnnnnnnnnnnnnnnnnnnnnnnnn nnnnnnnnnnnnnnnnnnnnnnnnnnnnnn: 30 character satellite name. SATELLITE FREQUCNCIES = FRQ The SET command requires an ASCII U followed by two five digit parameters separated by an ASCII - for the uplink band, an ASCII D followed by two five digit parameters separated by an ASCII - for the downlink band, and an ASCII X followed by a seven digit parameter or the character string EXTERNAL for the translation frequency. Remote Command Sequence: $FRQUlllll-hhhhhDlllll-hhhhhXfffffff Response: $FRQ The QUERY command requires no parameters. Remote Command Sequence:?FRQ Response:?FRQUlllll-hhhhhDlllll-hhhhhXfffffff lllll: Five digit low band edge frequency expressed in MHz. hhhhh: Five digit high band edge frequency expressed in MHz. fffffff: Seven digit translation frequency expressed in khz or the character string EXTERNAL if the translation frequency is supplied externally. ATTENUATION = ATT The SET command requires a three digit parameter which sets the attenuation of the translator in 0.2 db steps. The parameter is expressed in tenths of a db so no decimal point is required. Remote Command Sequence: $ATTttt Response: $ATT The QUERY command requires no parameters. Remote Command Sequence:?ATT Response:?ATTttt ttt: Attenuation in tenths of a db. ALARM STATUS = ALR There is no SET command. The QUERY command requires no parameters. Remote Command Sequence:?ALR Response:?ALRabcd 16
a through d are ASCII 0 or 1 and represent the fault alarms below. a: LO Alarm b: Power Supply Alarm c: not assigned d: not assigned STATUS ALL = STA 0 = No fault, 1 = Fault There is no SET command. The QUERY command requires no parameters. The response is a combination of the?nam,?frq,?att and?alr commands. Remote Command Sequence:?STA Response:?STANAMnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnFRQUlllll-hhhhhDlllll-hhhhhXfffffffATTtttALRabcd nnnnnnnnnnnnnnnnnnnnnnnnnnnnnn: 30 character name. lllll: Five digit low band edge frequency expressed in MHz. hhhhh: Five digit high band edge frequency expressed in MHz. fffffff: Seven digit translation frequency expressed in khz or the character string EXTERNAL if the translation frequency is supplied externally. ttt: Attenuation in tenths of a db. a through d are ASCII 0 or 1 and represent the fault alarms. CUSTOM SATELLITE ALIAS NAME = CUS The SET command requires a one or two digit parameter that specifies the CUSTOM satellite number to which the alias name will be assigned, and a second parameter that specifies the alias name of the custom satellite. Up to thirty characters are allowed for a custom satellite alias name. Embedded spaces are allowed. Trailing spaces are optional. Remote Command Sequence: $CUSc(c)Nnnnnn...nnnnn c(c) = One or Two digit custom satellite number N = Name indicator nnnnn...nnnnn: 1-30 character name. Response: $CUS 17
The QUERY command requires a one or two digit parameter that specifies the CUSTOM satellite number. Remote Command Sequence:?CUSc(c) Response:?CUSc(c)Nnnnnnnnnnnnnnnnnnnnnnnnnnnnnnn c(c) = One or Two digit custom satellite number N = Name indicator nnnnnnnnnnnnnnnnnnnnnnnnnnnnnn: 30 character alias satellite name SATELLITE TABLE = SAT There is no SET command. The QUERY command requires a four-digit parameter indicating the satellite table entry to be examined. If entry 0000 is selected, the unit returns the number of satellites in the table. Otherwise the unit responds with the satellite name and frequency specification. MUTE = MUT Remote Command Sequence:?SATssss Response:?SATtttt or?satnamnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnfrqulllll-hhhhhdlllll-hhhhhxfffffff ssss: Satellite number tttt: Total number of satellites in the table. nnnnnnnnnnnnnnnnnnnnnnnnnnnnnn: 30 character name. lllll: Five digit low band edge frequency expressed in MHz. hhhhh: Five digit high band edge frequency expressed in MHz. fffffff: Seven digit translation frequency expressed in khz or the character string EXTERNAL if the translation frequency is supplied externally. The SET command requires a single parameter which sets the mute status. Remote Command Sequence: $MUTm Response: $MUT The QUERY command requires no parameters. Remote Command Sequence:?MUT Response:?MUTm m: 0 = RF not muted 1 = RF muted 18
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COMMAND EXAMPLES With a translator set for address 41H (ASCII code A ) the following are typical commands to and responses from the translator. A. Set the attenuation to 24.6 db. Controller Command Translator Response {A$ATT246}F {A$ATT}i B. Check the alarms. The translator indicates a power supply alarm. Controller Command Translator Response {A?ALR}z {A?ALR1000}l RS422/485 BUS TERMINATION A jumper selectable 120 ohm termination may be placed across the Data terminals. Placing a jumper across E1 connects the resistor between the DATA OUT + and - terminals. E2 connects the resistor between the DATA IN + and - terminals. E1 and E2 are on the main control PC board inside the translator. RS232 RTS/CTS (Option 17C Only) When the translator is equipped with an RS232 remote bus interface, the RTS output and CTS input signals are internally connected together with a jumper plug. The jumper must be removed if it is necessary to use the RTS/CTS protocol. The jumper is located on the auxiliary PC board which is mounted onto the main control PC board. IEEE-488 REMOTE CONTROL The translator performs the basic Talker and Listener functions as specified in the IEEE-488 standard. It is also capable of sending a Service Request to the active IEEE-488 Controller and will respond with a status word when the Serial Poll Enable message is received. The messages to and from the translator are ASCII character strings terminated with CR, LF and EOI. The response time from command to acknowledge is 100 ms maximum. DEVICE ADDRESS/SERVICE REQUEST ENABLE SELECTION The remote control parameters can be accessed by pressing the B and C soft-keys from the control screen. To change the device address, press the B soft-key, scroll through the possible addresses (00-30) until the desired address is displayed, and press the ENT key or press the B soft key again to retain the former address. 20
To enable/disable the SRQ, press the C soft-key, use the scroll knob to toggle between service request enabled and disabled. Press the ENT key when the desired setting is displayed or press the C soft key again to retain the former setting. MESSAGE PROTOCOL The following paragraphs describe each of the command codes. Commands preceded by? are QUERY commands and those preceded by $ are SET commands. QUERY commands are used to examine system parameters remotely while SET commands are intended to modify system parameters. SET commands do not affect the translator s response when it is addressed to talk by the IEEE-488 Controller. QUERY commands determine the translator s response when it is addressed to talk by the IEEE-488 Controller. The context of the translator s response remains in effect until another QUERY command is received. The alarm QUERY command (?ALR) is in effect at power up as the default response. SATELLITE NAME = NAM The SET command has two forms. The first form specifies a satellite name only. The second form species a satellite name and frequency. A satellite name may appear more than once in the satellite tables. The only difference between these entries is the frequency associated with that name. When a satellite name appears in the list more than once, the first form of this command will select the first match found to that satellite name. The second form of this command can select any satellite in the list. Name Only Specified: The SET command requires that the name of the satellite be included as a parameter. Up to thirty characters are allowed for a satellite name. Names shorter than 30 characters are allowed. Embedded spaces are allowed. Trailing spaces are optional. Custom satellite names, custom satellite alias names as well as library satellite names can be used to select a satellite. Duplicate satellite names can exist in the satellite library and also in the custom satellite alias list. The search starts with the custom satellite list followed by the custom satellite alias list and finally the library satellite list. The first match found in this ordered search will be chosen. Name and Frequency Specified: The SET command requires a 30 character name and a frequency specification. The name must be 30 characters long. If the satellite name is less than 30 characters in length, trailing spaces must be appended to the name so that the total length of the name is 30 characters. Following the name is the ASCII string "FRQU" followed by two five digit parameters separated by an ASCII - for the uplink band, an ASCII D followed by two five digit parameters separated by an ASCII - for the downlink band, and an ASCII X followed by a seven digit parameter or the character string EXTERNAL for the translation frequency. 21
Remote Command Sequence: $NAMnnnnn...nnnnn or $NAMnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnFRQUlllll-hhhhhDlllll-hhhhhXfffffff nnnnn...nnnnn: 1-30 character name. nnnnnnnnnnnnnnnnnnnnnnnnnnnnnn: 30 character name. lllll: Five digit low band edge frequency expressed in MHz. hhhhh: Five digit high band edge frequency expressed in MHz. fffffff: Seven digit translation frequency expressed in khz or the character string EXTERNAL if the translation frequency is supplied externally. The QUERY command requires no parameters. Remote Command Sequence:?NAM Response when addressed as a talker:?namnnnnnnnnnnnnnnnnnnnnnnnnnnnnnn nnnnnnnnnnnnnnnnnnnnnnnnnnnnnn: 30 character satellite name. SATELLITE FREQUCNCIES = FRQ The SET command requires an ASCII U followed by two five digit parameters separated by an ASCII - for the uplink band, an ASCII D followed by two five digit parameters separated by an ASCII - for the downlink band, and an ASCII X followed by a seven digit parameter or the character string EXTERNAL for the translation frequency. Remote Command Sequence: $FRQUlllll-hhhhhDlllll-hhhhhXfffffff The QUERY command requires no parameters. Remote Command Sequence:?FRQ Response when addressed as a talker:?frqulllll-hhhhhdlllll-hhhhhxfffffff lllll: Five digit low band edge frequency expressed in MHz. hhhhh: Five digit high band edge frequency expressed in MHz. fffffff: Seven digit translation frequency expressed in khz or the character string EXTERNAL if the translation frequency is supplied externally. ATTENUATION = ATT The SET command requires a three digit parameter which sets the attenuation of the translator in 0.2 db steps. The parameter is expressed in tenths of a db so no decimal point is required. Remote Command Sequence: $ATTttt 22
The QUERY command requires no parameters. Remote Command Sequence:?ATT Response when addressed as a talker:?attttt ttt: Attenuation in tenths of a db. ALARM STATUS = ALR There is no SET command. The QUERY command requires no parameters. Remote Command Sequence:?ALR Response when addressed as a talker:?alrabcd a through d are ASCII 0 or 1 and represent the fault alarms below. a: LO Alarm b: Power Supply Alarm c: not assigned d: not assigned 0 = No fault, 1 = Fault STATUS ALL = STA There is no SET command. The QUERY command requires no parameters. The response is a combination of the?nam,?frq,?att and?alr commands. Remote Command Sequence:?STA Response when addressed as a talker:?stanamnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnfrqulllll-hhhhhdlllll-hhhhhxfffffffatttttalrabcd nnnnnnnnnnnnnnnnnnnnnnnnnnnnnn: 30 character name. lllll: Five digit low band edge frequency expressed in MHz. hhhhh: Five digit high band edge frequency expressed in MHz. fffffff: Seven digit translation frequency expressed in khz or the character string EXTERNAL if the translation frequency is supplied externally. ttt: Attenuation in tenths of a db. a through d are ASCII 0 or 1 and represent the fault alarms. 23
CUSTOM SATELLITE ALIAS NAME = CUS The SET command requires a one or two digit parameter that specifies the CUSTOM satellite number to which the alias name will be assigned, and a second parameter that specifies the alias name of the custom satellite. Up to thirty characters are allowed for a custom satellite alias name. Embedded spaces are allowed. Trailing spaces are optional. Remote Command Sequence: $CUSc(c)Nnnnnn...nnnnn c(c) = One or Two digit custom satellite number N = Name indicator nnnnn...nnnnn: 1-30 character name. The QUERY command requires a one or two digit parameter that specifies the CUSTOM satellite number. Remote Command Sequence:?CUSc(c) Response when addressed as a talker:?cusc(c)nnnnnnnnnnnnnnnnnnnnnnnnnnnnnnn c(c) = One or Two digit custom satellite number N = Name indicator nnnnnnnnnnnnnnnnnnnnnnnnnnnnnn: 30 character alias satellite name SATELLITE TABLE = SAT There is no SET command. The QUERY command requires a four-digit parameter indicating the satellite table entry to be examined. If entry 0000 is selected, the unit returns the number of satellites in the table. Otherwise the unit responds with the satellite name and frequency specification. Remote Command Sequence:?SATssss Response when addressed as a talker:?sattttt or?satnamnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnfrqulllll-hhhhhdlllll-hhhhhxfffffff ssss: Satellite number tttt: Total number of satellites in the table. nnnnnnnnnnnnnnnnnnnnnnnnnnnnnn: 30 character name. lllll: Five digit low band edge frequency expressed in MHz. hhhhh: Five digit high band edge frequency expressed in MHz. fffffff: Seven digit translation frequency expressed in khz or the character string EXTERNAL if the translation frequency is supplied externally. 24
SERVICE REQUEST The translator will issue a service request (activate the SRQ line) if the SRQ is enabled and one of the status alarms indicate a failure. The IEEE-488 Controller then performs a serial poll addressing the unit to talk. The following bits are reported back to the controller: Bit Number 7 6 5 4 3 2 1 0 0 1 0 0 d c b a a through d are 0 or 1 and represent the fault alarms below. a: LO Alarm b: Power Supply Alarm c: not assigned d: not assigned 0 = No fault 1 = Fault The IEEE-488 Controller may perform a serial poll without a service request being generated by the translator (a request may have been generated by another device on the bus). In this case, the message will have the same format with the exception that bit 6 will be a 0. REMOTE INTERFACE CONNECTION The remote interface connector(s) is located on the rear panel of the translator. The approximate location(s) is depicted in Figure 2. Figure 2. Universal Band Translator Rear Panel Diagram 25
RS422/485 REAR PANEL INTERFACE CONNECTOR J6 and J10 Pin Signal 1 Ground 3 Data Out - 5 Data In - 7 Data Out + 9 Data In + Note: For RS485 two wire party line operation Data In + must be externally wired to Data Out +, and Data In - must be externally wired to Data Out -. RS232 REAR PANEL INTERFACE CONNECTOR J6 Pin Signal 1 Ground 2 TX Data 3 RCV Data 7 Ground IEEE-488 REAR PANEL INTERFACE CONNECTOR IEEE-488 compatible contact connector (receptacle). SUMMARY ALARM CONNECTOR The summary connector, located on the rear panel, provides the status of the translator s alarm functions via a contact closure interface. The summary alarm connector pin designations are as follows: 1. DC Power Status - a. Normal: Pins 1-2 open,2-3 closed b. Fault: Pins 1-2 closed, 2-3 open 2. Summary Alarm Status - a. Normal (No Alarms): Pins 4-5 open,5-6 closed b. Fault (Any Alarm): Pins 4-5 closed, 5-6 open 26
REDUNDANCY SWITCH CONNECTOR The redundancy switch connector, located on the rear panel, provides a summary alarm output via a contact closure interface. This can be used in conjunction with a Redundancy Switchover Unit. The redundancy switch connector pin designations are as follows: 1. Summary Alarm Status - a. Normal (No Alarms): Pins 1-2 open,2-3 closed b. Fault (Any Alarm): Pins 1-2 closed, 2-3 open M:\TECHNOTE\25T022.DOC 27