DS28E04-100(3) One-Wire File System DS28E04-100(3)

# [NAME](#NAME)

**DS28E04** - 1-Wire EEPROM chip (4096-bit) with seven address inputs

# [SYNOPSIS](#SYNOPSIS)

4096-bit EEPROM, 2 port switch

**1C** \[.]XXXXXXXXXXXX\[XX]\[/\[ **latch.\[0-1|ALL|BYTE]** | **PIO.\[0-1|ALL|BYTE]** | **power** | **sensed.\[0-1|ALL|BYTE]** | **polarity** | **por** | **set\_alarm** |

See the file man3/standard\_mini.3so.

]]

# [FAMILY CODE](#FAMILY_CODE)

*1C*

# [SPECIAL PROPERTIES](#SPECIAL_PROPERTIES)

## [latch.0 latch.1 latch.ALL latch.BYTE](#latch.0_latch.1_latch.ALL_latch.BYTE)

*read-write, binary*  
The 2 pins (PIO) latch a bit when their state changes, either externally, or through a write to the pin.  
Reading the *latch* property indicates that the latch has been set.  
Writing any data to ANY *latch* will reset them all. (This is the hardware design).  
*ALL* is all *latch* states, accessed simultaneously, comma separated.  
*BYTE* references all channels simultaneously as a single byte. Channel 0 is bit 0.

## [PIO.0 PIO.1 PIO.ALL PIO.BYTE](#PIO.0_PIO.1_PIO.ALL_PIO.BYTE)

*read-write, yes-no*  
State of the open-drain output ( *PIO* ) pin. 0 = non-conducting = off, 1 = conducting = on.  
Writing zero will turn off the switch, non-zero will turn on the switch. Reading the *PIO* state will return the switch setting. To determine the actual logic level at the switch, refer to the *sensed.0 sensed.1 sensed.ALL sensed.BYTE* property.  
*ALL* references all channels simultaneously, comma separated.  
*BYTE* references all channels simultaneously as a single byte. Channel 0 is bit 0.

## [power](#power)

*read-only, yes-no*  
Is the *DS28E04* powered parasitically (=0) or separately on the Vcc pin (=1)?

## [sensed.0 sensed.1 sensed.ALL sensed.BYTE](#sensed.0_sensed.1_sensed.ALL_sensed.BYTE)

*read-only, yes-no*  
Logic level at the *PIO* pin. 0 = ground. 1 = high (~2.4V - 5V ). Really makes sense only if the *PIO* state is set to zero (off), else will read zero.  
*ALL* references all channels simultaneously, comma separated.  
*BYTE* references all channels simultaneously as a single byte. Channel 0 is bit 0.

## [polarity](#polarity)

*read-only, yes-no*  
Reports the state of the POL pin. The state of the POL pin specifies whether the PIO pins P0 and P1 power up high or low. The polarity of a pulse generated at a PIO pin is the opposite of the pin's power-up state.

*0*

PIO powers up 0

*1*

PIO powers up 1

## [por](#por)

*read-write, yes-no*  
Specifies whether the device has performed power-on reset. This bit can only be cleared to 0 under software control. As long as this bit is 1 the device will always respond to a conditional search.

## [set\_alarm](#set_alarm)

*read-write, integer unsigned (0-333)*  
A number consisting of 3 digits XYY, where:

[X](#X)

select source and logical term  
*0* PIO OR  
*1* latch OR  
*2* PIO AND  
*3* latch AND

[Y](#Y)

select channel and polarity  
*0* Unselected (LOW)  
*1* Unselected (HIGH)  
*2* Selected LOW  
*3* Selected HIGH

All digits will be truncated to the 0-3 range. Leading zeroes are optional. Low-order digit is channel 0.

Example:

133

Responds on Conditional Search when latch.1 or latch.0 are set to 1.

222

Responds on Conditional Search when sensed.1 and sensed.0 are set to 0.

000 (0)

Never responds to Conditional Search.

# [STANDARD PROPERTIES](#STANDARD_PROPERTIES)

See the file man3/standard.3so.

# [ALARMS](#ALARMS)

Use the *set\_alarm* property to set the alarm triggering criteria.

# [DESCRIPTION](#DESCRIPTION)

See the file man3/description.3so.

## [DS28E04](#DS28E04)

The [**DS28E04 (3)**](/man/os/owfs/DS28E04.3) is a memory chip that bends the unique addressing capabilities of the *1-wire* design. Some of the ID bits can be assigned by hardware.

# [ADDRESSING](#ADDRESSING)

See the file man3/addressing.3so.

# [DATASHEET](#DATASHEET)

http://pdfserv.maxim-ic.com/en/ds/DS28E04.pdf

# [SEE ALSO](#SEE_ALSO)

See the file man3/seealso.3so.

# [AVAILABILITY](#AVAILABILITY)

http://www.owfs.org

# [AUTHOR](#AUTHOR)

Paul Alfille (paul.alfille@gmail.com)

2003 OWFS Manpage

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Document: DS28E04(3) from owfs 3.2.4-r9 (Chainguard OS)
Source: https://github.com/owfs/owfs