| Online Development Notebook > Index > Programming Overview > Device Commands > Write1WireBit |
Write1WireBit - Write a bit to a 1-wire bus⁄device
VERSION 1.46+ of the firmware, VERSION 58+ of the DLL
Description:
This is a function to send a 1-wire (MicroLAN) bit write on the previously selected port pin.
Command Syntax: (USBm.dll)
USBm_Write1WireBit( device, data )
The USBm_Write1WireBit function syntax has these parts:
| Part | Description |
| device | A zero-based index to address the appropriate USB device. |
| data | Bit to write to bus (00h or 01h). |
Remarks:
This command does not set the port direction pins or select the pin to use as the 1-wire bus - it is the Reset1Wire command that does this.
VB Declaration
| Public Declare Function USBm_Write1WireBit _ Lib "USBm.dll" _ (ByVal device As Byte, _ ByVal data As Byte)_ As Integer |
VB Example
| USBm_Write1WireBit 3, 1 |
This code fragment addresses U4x1 device #3, and writes the bit value of 1 on the 1-wire bus (line to use previously selected by the Reset1Wire command).
C Prototype
| int USBm_Write1WireBit ( unsigned char device, unsigned char data ); |
C Example
| USBm_Write1WireBit ( 3, 1 ); |
This code fragment addresses U4x1 device #3, and writes the bit value of 1 on the 1-wire bus (line to use previously selected by the Reset1Wire command).
RobotBASIC
usbm_Write1WireBit(ne_DeviceNumber,ne_BitValue)
Returns true if successful, false otherwise. Writes a 0 or 1 to the 1wire device.
Raw Command Format:
| Byte Number | Description |
| 0 | 1Eh: Write1WireCmd |
| 1 | Data - Byte⁄bit to write. |
| 2 | Byte⁄bit - 0 = write byte, 1 = write bit. Bit feature for VERSION 1.30+ of the firmware |
| 3 | <not used> |
| 4 | <not used> |
| 5 | <not used> |
| 6 | <not used> |
| 7 | <not used> |
Raw Command Format Details:
Byte 0 contains the command. Byte 1 contains the data to write to the previously selected port line. the data is either a byte or a bit, depending on byte 2.
Byte 2 selects writing either a byte or a bit.
This command does not set the port direction pins or select the pin to use as the 1-wire bus - it is the Reset1Wire command that does this.
Raw Command Response Format:
| Byte Number | Description |
| 0 | 1Eh: Write1WireCmd |
| 1 | <not used> |
| 2 | <not used> |
| 3 | <not used> |
| 4 | <not used> |
| 5 | <not used> |
| 6 | <not used> |
| 7 | <not used> |
Raw Command Response Format Details:
Byte 0 contains the command. Byte 1 through byte 7 are unused.
Hardware: U401 USB Interface U421 USB Interface U451 USB Interface
Programming: USBm DLL Programming Download Files
Application Notes: U4x1 Application Notes Misc Applications and Information FAQ
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