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Serial Communication Products

Many types of external computer equipment have a serial ports to communicate with host PCs. ACCES I/O has Communication Cards for all of the popular protocols you may find on this type of equipment (RS-232, RS-422 and RS-485), ranging from a single port to eight ports on a single card. There are also optically isolated versions of some of these cards to ensure effective data transmission on long communication lines, even in electrically noisy environments. Having optical isolation is like having data insurance.

RS-485 and RS-422 have significant advantages over RS-232 as they use differential drivers instead of driving just one wire. This allows the cables in RS-485 and RS-422 applications to be up to 4000 feet, where RS-232 has a limit of 50 feet. See the table below for a comparison of cable length vs. baud rates.

PCIe PCI USB mPCIe PC/104 PCI-104, PC/104-Plus PC/104-Express Ethernet Watchdogs Converters
PCI Express Serial Communication Cards
 SERIAL PORTS
ProductsRS-232RS-422RS-485BaudPROT CFGISOLATIONLRG FIFOConnectorRoHS
RS232, RS422 & RS485 PCI Express Serial Cards
PCIe-COM-8SM*8 Software Selectable921.6k3EEPROM128-ByteCabled DB9
PCIe-COM-4SM* 4 Software Selectable921.6k3EEPROM128-ByteCabled DB9
PCIe-COM-4SMRJ4 Software Selectable921.6k3EEPROM 128-ByteRJ45
PCIe-COM-4SMDB4 Software Selectable921.6k3EEPROM 128-ByteDB9
PCIe-COM-2SMRJ2 Software Selectable921.6k3EEPROM 128-ByteDRJ45
PCIe-COM-2SMDB2 Software Selectable921.6k3EEPROM 128-ByteDB9
PCIe-ICM-4SM4 Software Selectable921.6k3EEPROMYes128-ByteDB9
PCIe-ICM-2SM2 Software Selectable921.6k3EEPROMYes128-ByteDB9
RS422 & RS485 PCI Express Serial Cards
PCIe-COM-4SRJ 4 Software Selectable921.6k3EEPROM 128-ByteRJ45
PCIe-COM-4SDB 4 Software Selectable921.6k3EEPROM 128-ByteDB9
PCIe-COM-2SRJ 2 Software Selectable921.6k3EEPROM 128-ByteRJ45
PCIe-COM-2SDB 2 Software Selectable921.6k3EEPROM 128-ByteDB9
PCIe-ICM-4S 4 Software Selectable921.6k3EEPROMYes128-ByteDB9
PCIe-ICM-2S 2 Software Selectable921.6k3EEPROMYes128-ByteDB9
RS232 Only PCI Express Serial Cards
PCIe-COM232-8**8  921.6k128-ByteCabled DB9
PCIe-COM232-4**4  921.6k128-ByteCabled DB9
PCIe-COM232-4RJ4  921.6k 128-ByteRJ45
PCIe-COM232-4DB4  921.6k 128-ByteDB9
PCIe-COM232-2RJ2  921.6k 128-ByteRJ45
PCIe-COM232-2DB2  921.6k 128-ByteDB9
PCIe-ICM232-44  921.6kYes128-ByteDB9
PCIe-ICM232-22  921.6kYes128-ByteDB9
RS422 Only PCI Express Serial Cards
PCIe-COM422-8*8921.6k3EEPROM128-ByteCabled DB9
PCIe-COM422-4* 4921.6k3EEPROM128-ByteCabled DB9
RS485 Only PCI Express Serial Cards
PCIe-COM485-8*8921.6k3EEPROM128-ByteCabled DB9
PCIe-COM485-4* 4921.6k3EEPROM128-ByteCabled DB9
Isolated PCI Express Serial Cards
PCIe-ICM-4SM4 Software Selectable921.6k3EEPROMYes128-ByteDB9
PCIe-ICM-2SM2 Software Selectable921.6k3EEPROMYes128-ByteDB9
PCIe-ICM-4S 4 Software Selectable921.6k3EEPROMYes128-ByteDB9
PCIe-ICM-2S 2 Software Selectable921.6k3EEPROMYes128-ByteDB9
PCIe-ICM232-44  921.6kYes128-ByteDB9
PCIe-ICM232-22  921.6kYes128-ByteDB9
PROT CFG = protocol configuration * Low Profile MD2 PCI/PCIe spec ** Low Profile MD1 = Smallest PCI/PCIe specification = Optionally available RoHS Ready 3 = Up to 3Mbps with custom software

Mini-PCI Express (mPCIe) Serial Communication Cards
 SERIAL PORTS
ProductsRS-232RS-422RS-485BaudPROT CFGISOLATIONLRG FIFOConnectorRoHS
RS232, RS422 & RS485 PCI Express Mini Serial Cards
mPCIe-COM-4SM
4 Software Selectable921.6k3EEPROM 128-Bytemicro header + cable
mPCIe-COM-2SM
2 Software Selectable921.6k3EEPROM 128-Bytemicro header + cable
RS422 & RS485 PCI Express Mini Serial Cards
mPCIe-COM-4S
 4 Software Selectable921.6k3EEPROM 128-Bytemicro header + cable
mPCIe-COM-2S
 2 Software Selectable921.6k3EEPROM 128-Bytemicro header + cable
RS422 ONLY PCI Express Mini Serial Cards
mPCIe-ICM422-4
 4 3MbpsYes128-Bytemicro header + cable
mPCIe-ICM422-2
 2 3MbpsYes128-Bytemicro header + cable
mPCIe-ICM422-1
 1 3MbpsYes128-Bytemicro header + cable
RS485 ONLY PCI Express Mini Serial Cards
mPCIe-ICM485-4
  43MbpsYes128-Bytemicro header + cable
mPCIe-ICM485-2
  23MbpsYes128-Bytemicro header + cable
mPCIe-ICM485-1
  13MbpsYes128-Bytemicro header + cable
RS232 ONLY PCI Express Mini Serial Cards
mPCIe-ICM232-4
4  921.6kYes128-Bytemicro header + cable
mPCIe-ICM232-2
2  921.6kYes128-Bytemicro header + cable
mPCIe-COM232-4
4  921.6k 128-Bytemicro header + cable
mPCIe-COM232-2
2  921.6k 128-Bytemicro header + cable
Other PCI Express Mini Serial Cards
mPCIe-CAN-2
Coming Soon!		1 Dual-Wire CAN-bus port25k-1MBitn/amicro header + cable
mPCIe-1394B-1
Coming Soon!		1 Port 1394B interface
aka FireWire 800		800 Mbit/sn/amicro header + cable
Isolated PCI Express Mini Serial Cards
mPCIe-ICM485-4
  43MbpsYes128-Bytemicro header + cable
mPCIe-ICM422-4
 4 3MbpsYes128-Bytemicro header + cable
mPCIe-ICM232-4
4  921.6kYes128-Bytemicro header + cable
mPCIe-ICM485-2
  23MbpsYes128-Bytemicro header + cable
mPCIe-ICM422-2
 2 3MbpsYes128-Bytemicro header + cable
mPCIe-ICM232-2
2  921.6kYes128-Bytemicro header + cable
mPCIe-ICM485-1
  13MbpsYes128-Bytemicro header + cable
mPCIe-ICM422-1
 1 3MbpsYes128-Bytemicro header + cable
PROT CFG = protocol configuration *mPCIe full-length ** mPCIe half-length = Smallest mPCIe specification = Optionally available RoHS Ready

M.2 Express Serial Communication Cards
 SERIAL PORTS
ProductsRS-232RS-422RS-485BaudPROT CFGISOLATIONLRG FIFOConnectorRoHS
RS232, RS422 & RS485 M.2 Serial Cards
M.2-COM-4SM
4 Software Selectable921.6k3EEPROM 128-Bytemicro header + cable
M.2-COM-2SM
2 Software Selectable921.6k3EEPROM 128-Bytemicro header + cable
RS422 & RS485 M.2 Serial Cards
M.2-COM-4S
 4 Software Selectable921.6k3EEPROM 128-Bytemicro header + cable
M.2-COM-2S
 2 Software Selectable921.6k3EEPROM 128-Bytemicro header + cable
RS422 ONLY M.2 Serial Cards
M.2-ICM422-4
 4 3MbpsYes128-Bytemicro header + cable
M.2-ICM422-2
 2 3MbpsYes128-Bytemicro header + cable
M.2-ICM422-1
 1 3MbpsYes128-Bytemicro header + cable
RS485 ONLY M.2 Serial Cards
M.2-ICM485-4
  43MbpsYes128-Bytemicro header + cable
M.2-ICM485-2
  23MbpsYes128-Bytemicro header + cable
M.2-ICM485-1
  13MbpsYes128-Bytemicro header + cable
RS232 ONLY M.2 Serial Cards
M.2-ICM232-2
2  921.6kYes128-Bytemicro header + cable
M.2-ICM232-4
4  921.6kYes128-Bytemicro header + cable
M.2-COM232-4
4  921.6k 128-Bytemicro header + cable
M.2-COM232-2
2  921.6k 128-Bytemicro header + cable
Other M.2 Serial Cards
M.2-CAN-2
Coming Soon!		1 Dual-Wire CAN-bus port25k-1MBitn/amicro header + cable
M.2-1394B-1
Coming Soon!		1 Port 1394B interface
aka FireWire 800		800 Mbit/sn/amicro header + cable
Isolated M.2 Serial Cards
M.2-ICM485-4
  43MbpsYes128-Bytemicro header + cable
M.2-ICM422-4
 4 3MbpsYes128-Bytemicro header + cable
M.2-ICM232-4
4  921.6kYes128-Bytemicro header + cable
M.2-ICM485-2
  23MbpsYes128-Bytemicro header + cable
M.2-ICM422-2
 2 3MbpsYes128-Bytemicro header + cable
M.2-ICM232-2
2  921.6kYes128-Bytemicro header + cable
M.2-ICM485-1
  13MbpsYes128-Bytemicro header + cable
M.2-ICM422-1
 1 3MbpsYes128-Bytemicro header + cable
PROT CFG = protocol configuration *mPCIe full-length ** mPCIe half-length = Smallest mPCIe specification = Optionally available RoHS Ready
PCIe/104 (104e) Serial Communication Cards Preliminary - subject to change
 SERIAL PORTS
ProductsRS-232RS-422RS-485BaudPROT CFGISOLATIONLRG FIFOConnectorRoHS
104e-COM-8SM
Coming Soon!		8 Software Selectable921.6k3EEPROM128-ByteCabled DB9
104e-COM485-8
Coming Soon!		8921.6k3EEPROM128-ByteCabled DB9
104e-COM422-8
Coming Soon!		8921.6k3EEPROM128-ByteCabled DB9
104e-COM-4S
Coming Soon!		 4 Software Selectable921.6k3EEPROM 128-ByteCabled DB9
104e-COM232-4
Coming Soon!		4  921.6k 128-ByteCabled DB9
104e-COM-2SM
Coming Soon!		2 Software Selectable921.6k3EEPROM 128-ByteCabled DB9
104e-COM-2S
Coming Soon!		 2 Software Selectable921.6k3EEPROM 128-ByteCabled DB9
104e-COM232-2
Coming Soon!		2  921.6k 128-ByteCabled DB9
104e-ICM-2SM
Coming Soon!		2 Software Selectable921.6k3EEPROMYes128-ByteCabled DB9
104e-ICM-2S
Coming Soon!		 2 Software Selectable921.6k3EEPROMYes128-ByteCabled DB9
104e-ICM232-2
Coming Soon!		2  921.6kYes128-ByteCabled DB9
PROT CFG = protocol configuration = Optionally available RoHS Ready
PC/104 (ISA only) Serial Communication DAQ Products
  SERIAL PORTS OPTIONS
Products RS-232 RS-422 RS-485 Baud PROT CFG ADDR CFG LRG FIFO XT
RS232, RS422 & RS485 PCI Express Mini Serial Cards
104-COM-8SM888921.6kJumperJumperYesYes
104-COM-4SM444921.6kJumperJumperYesYes
104-COM-2SM222921.6kJumperJumperYesYes
RS422 & RS485 PCI Express Mini Serial Cards
104-COM-8S 88921.6kJumperJumperYesYes
104-COM-4S 44921.6kJumperJumperYesYes
104-COM-2S 22921.6kJumperJumperYesYes
104-ICOM-2S* 22115.2kJumperJumperYesYes
RS232 ONLY PCI Express Mini Serial Cards
104-COM232-88  230.4k JumperYesYes
104-COM232-44  230.4k JumperYesYes
104-COM232-22  230.4k JumperYesYes
Isolated PCI Express Mini Serial Cards
104-ICOM-2S* 22115.2kJumperJumperYesYes
PROT CFG = protocol configuration   XT = extended temperature option   * optically isolated and optional 460.8k baud rate
PCI-104 (no ISA connector) and PC/104-Plus (ISA, PCI) Serial Communication DAQ Products
  SERIAL PORTS OPTIONS
Products RS-232 RS-422 RS-485 Baud PROT CFG ADDR CFG LRG FIFO XT
RS232, RS422 & RS485 PCI-104 & PC/104-Plus Serial Cards
104I-COM-8SM8881.8432Mbps**JumperJumperYesYes
104I-COM-4SM4441.8432Mbps**JumperJumperYesYes
104I-COM-2SM2221.8432Mbps**JumperJumperYesYes
RS422 & RS485 PCI-104 & PC/104-Plus Serial Cards
104I-COM-8S 881.8432MbpsJumperJumperYesYes
104I-COM-4S 441.8432MbpsJumperJumperYesYes
104I-COM-2S 221.8432MbpsJumperJumperYesYes
RS232 ONLY PCI-104 & PC/104-Plus Serial Cards
104I-COM232-88  460.8k SoftwareYesYes
104I-COM232-44  460.8k SoftwareYesYes
104I-COM232-22  460.8k SoftwareYesYes
P104-COM232-8*8  460.8k SoftwareYesYes
PROT CFG = protocol configuration   XT = extended temperature option  
*PC/104-Plus (PCI and ISA connector)   **Up to 921.6k RS-232
PCI Bus Serial Products
 SERIAL PORTSOPTIONS
ProductsRS-232RS-422RS-485BaudPROT CFGLOW PROFLRG FIFORoHS
RS232, RS422 & RS485 PCI Serial Cards
LPCI-COM-8SM888921.6kJumperYes 
LPCI-COM-4SM444921.6kJumperYes 
RS422 & RS485 PCI Serial Cards
PCI-422/485-2 22460.8kJumper Yes
PCI-COM-2S222460.8kJumper Yes
PCI-ICM-2S* 22460.8kJumper Yes
LPCI-COM-1S 11460.8kJumperYesYes
PCI-ICM-1S* 11460.8kJumper Yes
RS422 ONLY PCI Serial Cards
LPCI-COM422-8 8 921.6kFixedYesYes
PCI-COM422/4 4 460.8kFixed Yes
PCI-ICM422/4* 4 460.8kFixed Yes
RS485 ONLY PCI Serial Cards
LPCI-COM485-8  8921.6kFixedYesYes
PCI-COM485/4  4460.8kFixed Yes
PCI-ICM485/4*  4460.8kFixed Yes
RS232 ONLY PCI Serial Cards
LPCI-COM232-88  921.6kFixedYes 
PCI-COM232/44  115.2kFixed  
LPCI-COM232-44  921.6kFixedYes 
PCI-COM232/22  115.2kFixed  
Isolated PCI Serial Cards
PCI-ICM485/4*  4460.8kFixed Yes
PCI-ICM-2S* 22460.8kJumper Yes
PCI-ICM-1S* 11460.8kJumper Yes
PROT CFG = protocol configuration | LOW PROF = low profile form factor
* optically isolated | = Optionally available RoHS Ready

Serial Converter Products
MODELDESCRIPTIONRoHS
CONV232/485RS-232 to RS-485 Serial Communications Adapter
CONV232/422RS-232 to RS-422 or four-wire RS-485 Serial Communications Adapter

USB Serial Products
MODELDESCRIPTIONRoHS
ANDROID-232Board provides a bridge between RS-232 serial devices and an Android platform. Use your Android phone or tablet to control serial devices via the USB port. - New Product!
USB-232-INDRugged, extended temperature, single USB to RS-232 serial port adapter
USB-422-INDRugged, extended temperature, single USB to RS-422 serial port adapter
USB-485-INDRugged, extended temperature, single USB to RS-485 serial port adapter
USB-422-485-INDRugged, extended temperature, single USB to RS-485 4-wire serial port adapter. Pinout compatible with legacy model USB-485
USB-COM-2SMTwo-port USB to serial RS-232/422/485 adapter
USB-FLEXCOM4Four-Port Serial Communications adapter for Universal Serial Bus
USB-COM232-4AFour-Port Serial RS-232 Communications adapter for Universal Serial Bus
USB-IIRO4-2SMTwo-Port USB to Serial RS-232/422/485 adapter with 4 Electromechanical relays and 4 optically isolated inputs.

Ethernet Serial Products
MODELDESCRIPTIONRoHS
eNET-232-1Single-Port Ethernet-to-Remote RS-232 Serial Interface Device
eNET-422-1Single-Port Ethernet-to-Remote RS-422 Serial Interface Device
ETH-01
New Product!		Single-Port Ethernet-to-Remote RS-422/-485 Embeddable / OEM Serial Interface Module

Watchdog Products
MODELDESCRIPTIONRoHS
WDG-SIOWatchdog Timer and RS422/485 Serial Communications Card
WDG-2SWatchdog Timer and Dual RS422/RS485 Serial Communications Card

Baud Rate vs Cable Length*
Baud Rate Standard Divisor Divisor x4 Divisor x8 Maximum Differential Cable Length*
921600 - - 1 250 ft.
460800 - 1 2 500 ft.
230400 - 2 4 1400 ft.
153600 - 3 6 2500 ft.
115200 1 4 8 3000 ft.
57600 2 8 16 4000 ft.
38400 3 12 24 4000 ft.
28800 4 16 32 4000 ft.
19200 6 24 48 4000 ft.
14400 8 32 64 4000 ft.
9600 12 48 96 4000 ft.
4800 24 96 192 4000 ft.
2400 48 192 384 4000 ft.
1200 96 384 768 4000 ft.
*These are theoretical maximums based on typical conditions and good quality cables based on the EIA 485 and EIA 422 standard for balanced differential drivers.

Acquisition, Control, Communication: Engineering and Systems