 The HA7MP is a host adapter for Palm handhelds that provides an
RS232 to 1-Wire interface in an ABS enclosure. The HA7MP is designed
to provide an ASCII command set for Palm Pilot applications that need to
accommodate Dallas Semiconductor iButton and 1-Wire devices. The HA7MP relieves
the Palm Pilot of the burden of generating the time-critical 1-Wire communication
waveforms while supporting all 1-Wire devices with simple ASCII commands that can
be easily generated. The HA7MP does all the hard work of interfacing 1-Wire devices
and iButtons.
Rugged construction and ESD Protection of more than 27kV allow the HA7MP to be used
in harsh environments. Very low power consumption as well as automatic power-up
and power-down features allow the HA7MP to operate with a minimum of drain on the
Palm batteries and with no need for power control signals. The only interface signal
required is the RS232 level TX, RX, DTR, or RTS from the Palm serial port.
The HA7MP powers up into a very low energy state. When a serial ASCII command is
sent it will wake-up, process the command, send the response and power down.
The 1-Wire bus can be left in a powered up or a powered down state while the HA7MP
is powered down. While in power down mode it has a very low quiescent current
requirement.
The HA7MP can perform Search and Family Search functions making it easy to acquire
the unique 64 bit serial numbers of all connected 1-Wire devices. Many sensor devices require
that extra power be delivered during periods of data conversions (DS1920 and DS1820
temperature sensors for example). The HA7MP automatically provides the extra current
these devices require with a built in smart strong-pull-up. Dallas Semiconductor iButtons which store data in TMEX Touch Memory File format can be read or written
with simple ASCII commands. The HA7MP will automatically generate and check the
CRC16 error checks from Touch Memory File records. The HA7MP supports analog, digital,
and temperature 1-Wire devices and all Dallas Semiconductor iButtons.
The HA7MP-2 and HA7MP-3 may be used to charge the Palm, with the addition of
an optional power supply. This avoids the requirement of docking Palms
which have a Wi-Fi connection.
Features
- ASCII command support for all 1-Wire devices.
- Onboard Palm charging possible with addition of optional power supply
(HA7MP-2 & HA7MP-3 models only).
- Parasitically powered from Palm Serial Port.
- Automatically provides smart strong-pull-up.
- Automatic Power Management to extend battery life.
- RJ-11 connector for standard 1-Wire connection.
- Provides Search, Conditional Search and Family Search commands.
- Block mode commands support all 1-Wire device functions.
- Automatic CRC16 for TMEX files.
- Supports Touch Memory File Structure for Dallas Semiconductor iButtons
- ESD Protection more than 27kV (IEC801-2 Reference Model.) on the 1-Wire
bus.
Specifications
- Supply Current (active): 9-12 mA
- Supply Current (powered down): 90-150 MicroAmp
- 1-Wire Devices: 100 devices
- CAT-5 Cable length: 1000 feet
- Communications: RS232 9600,N,8,1 Baud
| Supported
Palm Models |
|
|
| HA7MP-1 & HA7MP-2 |
HA7MP-3 |
|
- Palm i705
- Palm m series: m125, m130, m500, m505, m515
- Tungsten series: T, T2, T3, C, W
- Zire 71
|
- Tungsten E2
- Tungsten T5
- TX
|
|
iButton and 1-Wire are registered trademarks of Dallas Semiconductor Corporation.
TMEX is a trademark of Dallas Semiconductor Corporation.
|
