Register Offset The register offset is the register’s location in the block of 64 address bytes. For example, with a LADDR of 112 the multiplexer’s Scan Channel Delay Register has an offset of 0816. When you write a command to this register, the offset is added to the base address to form the register address:

DC0016 + 0816 = DC0816

(A16 outside the command module)

1FDC0016 + 0816 = 1FDC0816

(A16 inside the command module)

or

 

56,320 + 8 = 56,328

(A16 outside the command module)

2,087,936 + 8 = 2,087,944

(A16 inside the command module)

Register Descriptions

There are six WRITE and two READ-only registers on the multiplexer. You can READ-back three of the WRITE registers. This section contains a description and a bit map of each register. Note that the bit names with an * after them are True (asserted) when low (zero). An X represents a "do not care" situation and a 1 always represents 1.

WRITE Registers The following WRITE registers are located on the multiplexer:

Status/Control Register (base + 0416)

Scan Control Register (base + 0616)

Scan Channel Delay Register (base + 0816)

Scan Channel Configuration Register (base + 0A16)

Direct Channel Configuration Register (base + 0C16)

Direct Control Register (base + 0E16)

READ Registers There are two READ-only registers and three READ-back registers.

Manufacturer ID Register (base + 0016) READ-only

Device Type Register (base + 0216) READ-only

Status/Control Register (base + 0416)

Scan Control Register (base + 0616)

Scan Channel Delay Register (base + 0816)

Manufacturer ID Register

base + 0016

15

14

13

12

11

10

9

8

7

 

6

5

 

4

3

2

1

0

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Write

 

 

 

 

 

 

 

Undefined

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Read

Device

Address

 

 

 

 

 

Manufacturer ID

 

 

 

 

 

 

Class

Space

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

84 HP E1351A/53A Register-Based Programming

Appendix B