Agilent Technologies 6621A, 6627A, 6622A manual Functional Relationship of Status Registers, Unr +Cc

Figure 5-3. Functional Relationship of Status Registers

The supply has one serial poll register which services all outputs and provides the user with other power supply status- related information as discussed on page 75.

Status Register. Each output channel of the power supply maintains its present status in an 8-bit register. This status register reports the status of the output channel whenever it is queried. A "1" in any of the bit positions indicates that the condition is true. As long as the condition continues to be true, the bit will remain set. Assignments for the bits are shown in Table 5-5.

Decoding of the reading is based on the weighted number placed on each bit of the 8-bit status registers. For example, bit position 5 in the register has a bit weight of 32 (see Table 5-5). Each bit is assigned to a particular condition and the corresponding bit weight is used to identify that condition. When set, bit 5 indicates that the associated output is in the unregulated state. If this is the only bit that is set, the number 32 will be returned when the output’s status register is queried.

	Table 5-5. Bit Alignment for the Status, A Status, Fault, and Mask Register
Bit Position	7	6	5	4	3	2	1	0
Bit Weight	128	64	32	16	8	4	2	1
Meaning	CP	OC	UNR	OT	OV	-CC	+CC	CV
Where

CV = Constant Voltage Mode

+CC = Positive Constant Current Mode - CC = Negative Current Limit Mode

OV = Overvoltage Protection circuit tripped

OT = Over Temperature Protection circuit tripped UNR = Unregulated Mode

OC = Over Current Protection tripped CP = Coupled parameter (See Note)

Note: When the range is automatically switched as discussed on page70, the CP bit is set. It is cleared when you send a voltage or current value that causes no range change.

Remote Operation 73