BOP HIPWR 111315 3-653.6.7 STATUS REPORTINGThe status reporting of the BOP power supply follows the SCPI and IEEE 488.2 requirements.The serial poll response of the BOP power supply provides summary bits of the status and errorreporting system. The simplest status report is the command valid reporting and data availabil-ity, This successful decoding of a command string generates no error and is indicated by the bit3 of the serial poll response being a zero. The setting of bit 4 in the status byte indicates data isavailable to the controller in response a command query message.3.6.7.1 STATUS REPORTING STRUCTUREThe status reporting of the BOP uses four status registers, illustrated in Figure 3-20. These reg-isters are the Questionable, Operation, Standard Event and Service Request registers. TheQuestionable and Operation registers are 16 bit registers and the Standard Event and ServiceRequest registers are 8 bits. These four registers are referred to as condition registers. Each ofthe four condition registers is associated with two related registers: an event register whichholds unlatched events reported in real-time by the instrument and is cleared by reading theregister, and an enable register which allows the contents of the event register to be passedthrough to set the associated condition register.A zero to one transition of a condition register is added to the event register. Reading an eventregister clears all of the bits found in the event register. If any bits are set in an event register,the following condition register bit is then set. For example, if the STAT:QUES:ENB (enable) reg-ister has bit 0 set and a voltage error is detected, the event registers bit 0 is set. The 1 in theevent register causes bit 3 of the status byte to be asserted. The Service Request register isANDed with its enable register for all bits except bit 6. The result is placed in bit 6 of the ServiceRequest register. If bit 6 is a 1 (true), it causes the power supply to assert the SRQ line to thehost controller.Figure 3-20 also shows that if the error/event queue is not empty, bit 3 is set in the ServiceRequest register and bit 4 indicates that a message is available in the output buffer.3.6.7.2 OPERATIONAL STATUS REGISTERThe OPERational condition register contains conditions which are a part of the instrument’s nor-mal operation. The definition of each of these bits (condition register) is as follows:• 0 through 4 - Not Used — always zero.• 5 - Waiting for Trigger — 1 indicates the trigger system is enabled. If trigger source isexternal and the trigger input goes low, the WTG will remain in a one condition untilafter the trigger input goes high.• 6 - Transient Armed — 1 indicates the transient function is enabled,• 7 - Not Used — always zero.• 8 - Constant Voltage — 1 indicates the instrument is in constant voltage mode.• 9 - Transient Complete — 1 indicates transient has been completed. Not readable inOPERation Status Condition register.• 10 - Constant Current — 1 indicates the instrument is in constant current mode.• 11 - Sample Complete — 1 indicates the sample has been completed.
