Individual Bits In Registers
Individual bits in registers are
X indicates an address is hexadecimal. If the X is not present, the address is read as decimal.
R indicates a Register address follows. 
nnnnis the actual address. Four characters are required, so leading zeroes must be used if necessary. For example, the correct syntax is 0025 rather than 25.
R <f> <[X]nnnn>DL-B
f indicates the register type.
D stands for Discrete type specifier, and indicates that bit data is being requested.
B indicates the starting bit number.
L indicates the specific number of bits being requested.
Examples
Register | Represents |
Number |
|
Specifies least significant bit of first holding register | |
|
|
Specifies most significant bit of an input register | |
|
|
Specifies 6th and 7th from the least significant bit of first holding | |
| register. |
|
|
DDE Server User’s Guide | Appendix A – Register Addressing Conventions • 83 |