B&B Electronics RS-485 manual States = states and NOTmask, Addr = 5 states =

Example 5.4 – Change the address of a model from 5 to 10. addr = 5

newaddr = 10

Command$ = “!” + CHR$(addr) + “SA” + CHR$(newaddr) Print #1, Command$

Set Power-up States Command

The Set Power-up States command is used to set the states of the digital outputs at power-up. This command requires a data byte. The data byte is used to specify the power-up output states. Bits 0-2 correspond to the power-up states of digital outputs 0-2. If a bit is a 0 then the output will be set LOW at power-up. If a bit is a 1 then the output will be set HIGH at power-up. Refer to Table 3.6.

NOTE: This command ignores bits 3-7 of the data byte.

The steps to setting a module’s power up states are given below:

1)Construct the command string:

a)Set appropriate outputs HIGH states = states OR mask

By “ORing” the current states with the appropriate mask of a digital output given in Table 5.1, the output’s data bit will be set to a “1” (HIGH).

b)Set appropriate outputs LOW

states = states AND (NOT(mask))

By “ANDing” the current states with the complement of the appropriate mask of a digital output given in Table 5.1, the output’s data bit will be set to a “0” (LOW).

c) Construct the string

Command$ = “!” + CHR$(addr) + “SS” + CHR$(states) Where addr is the module’s address.

2)Transmitting the command string:

Print #1, Command$

Example 5.5 – Set digital outputs 0 and 1 HIGH and digital output 2 LOW on the module with address 5.

addr = 5 states = 0

‘Set bit 0 of states to make digital output 0 HIGH states = states OR 1

‘Set bit 1 of states to make digital output 1 HIGH states = states OR 2

26 485SDA103798 Manual

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