Setup Software
Installation
Operation
& Specifications
Manual
620-0018 R2 © Micro
fl
ex 2016, 2021
101-0029
MicroLinK HM
RS-232 HART Protocol Modem
HART Device to Modbus Accumulator
DIN Rail Mount
The MicroLink-HM 101-0029 is an RS-232 to HART® protocol modem with managed HART master ming to func on
as either a primary or secondary HART master - elimina ng the need for external CD monitoring and RTS control.
It can also be used as a HART to Modbus Concentrator polling up to 16 HART devices. Power can be taken from the
serial port DTR handshake line or an external 5 to 30 volts DC power supply.
When used as a HART protocol modem it provides the hardware interface between Highway Addressable Remote
Transducer devices (HART) and a computer with an RS-232 port. Unlike many HART modems, communica ons
direc on control is handled internally so there is no need to handle tricky request-to-send (RTS) handshake ming,
greatly simplifying so ware development and enabling the MicroLink-HM modem to be compa ble with common
USB to RS-232 serial converters. Serial port baud rates can be set from 1200 to 57,600 and parity can be odd, even,
or none. HART protocol communica ons between the MicroLink-HM and HART devices is always 1200 baud, odd
parity.
MicroLink-HM can be con
fi
gured to poll up to 16 HART devices and save the HART device data into modbus
registers. Modbus RTU commands can then be used to read the HART device data. Con
fi
gura on is simple
using the included MicroLink-HM Con
fi
gura on so ware. Se ngs are saved in modus registers so modbus RTU
commands can also be used to edit the MicroLink se ngs. No special con
fi
gura on cable is needed for setup as
communica ons is done using the MicroLink-HM serial port.
