HP E1368A manual Addressing the Registers, Reading the Registers, ID and Device Type Registers

n

Addressing the Registers

To read or write to specific registers, you must use the register address. Register addresses for HP 75000 Series C plug-in modules are in address space VXI A16. The locatio of A16 within the mainframe/command module memory map depends on the mainframe/command module used. For example, the A16 location of the HP E1300/E1301 Mainframe starts at 1F000016 (16 = HEX).

The A16 space is divided so modules are addressed only at locations beginning with C00016 within A16. Allocated for each module are 64 register addresses (4016). The module base address is related to the logical address set by the module’s logical address switch (LADDR). The module address is:

module address 16 = (logical address 16) * 4016 + C00016

For the Microwave Switch modules, the default logical address is 120 (7816), thus the module address within A16=

7816 * 4016 + C00016 = DE0016

For example, to address the Status/Control Register of a Microwave Switch module in an HP E1300/E1301 Mainframe, the command register address is:

[A16 location]16 + [module address]16 + [register offset]16 = 1f00016 + DE0016 + 0416 = 1FDE0416

Reading the Registers

ID and Device Type Registers

You can read the following Microwave Switch registers:

∙Manufacturer ID Register (base + 0016)

∙Device Type Register (base + 0216)

∙Status/Control Register (base + 0816)

∙Channel Enable Register (base + 0816)

ID Register: Reading the register returns: FFFF16. This shows Hewlett-Packard as the manufacturer and that the module is an A16 register-based device.

Device Type Register: Reading this register returns FF2816 if the device is either the E1368A Microwave Switch module, or the E1369A Microwave Switch Driver module.

76 HP E1368A/69A/70A Registers Appendix B