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Serial Communication Products

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  US Prices
CDN Prices

Privacy and Security Policy

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.




Products RS-232 RS-422 RS-485 Baud PROT CFG ADDR CFG LRG FIFO XT Price/Buy
104-COM232-2 2     230.4k   Jumper Yes Yes  
104-COM232-4 4     230.4k   Jumper Yes Yes  
104-COM232-8 8     230.4k   Jumper Yes Yes  
P104-COM232-8 8     460.8k   Software Yes Yes  
104-COM-2S   2 2 115.2k Jumper Jumper Yes Yes  
104-ICOM-2S*   2 2 115.2k Jumper Jumper Yes Yes  
104-COM-2SM 2 2 2 921.6k Jumper Jumper Yes Yes  
104-COM-4SM 4 4 4 921.6k Jumper Jumper Yes Yes  
104-COM-8S   8 8 921.6k Jumper Jumper Yes Yes  
104-COM-8SM 8 8 8 921.6k Jumper Jumper Yes Yes  
PROT CFG = protocol configuration
XT = extended temperature option * optically isolated

Products RS-232 RS-422 RS-485 Baud PROT CFG LOW PROF LRG FIFO Price/Buy
LPCI-COM-1S   1 1 460.8k Jumper Yes Yes  
PCI-ICM-1S*   1 1 460.8k Jumper   Yes  
PCI-ICM-2S*   2 2 460.8k Jumper   Yes  
PCI-422/485-2   2 2 460.8k Jumper   Yes  
PCI-COM-2S 2 2 2 460.8k Jumper   Yes  
PCI-COM232/2 2     921.6k Fixed      
PCI-COM232/4 4     921.6k Fixed      
LPCI-COM232-4 4     230.4k Fixed Yes    
LPCI-COM-4SM 4 4 4 921.6k Jumper Yes    
PCI-COM422/4   4   115.2k Fixed   Yes  
PCI-ICM422/4*   4   460.8k Fixed   Yes  
PCI-COM485/4     4 921.6k Fixed   Yes  
PCI-ICM485/4*     4 460.8k Fixed   Yes  
LPCI-COM232-8 8     230.4k Fixed Yes    
LPCI-COM422/8   8   921.6k Fixed Yes Yes  
LPCI-COM485/8     8 921.6k Fixed Yes Yes  
LPCI-COM-8SM 8 8 8 921.6k Jumper Yes    
PROT CFG = protocol configuration
LOW PROF = low profile form factor * optically isolated

Converters image CONV232/485 RS-232 to RS-485 Serial Communications Adapter    
CONV232/422 RS-232 to RS-422 or four-wire RS-485 Serial Communications Adapter    
usb USB-232,
and USB-485
Add a single RS-232, RS-422 or RS-485 serial port to any USB equipped computer    
and USB-485
Single USB to RS-232, RS-422 or RS-485 serial port adapter    
USB-COM-2SM Two-port USB to serial RS-232/422/485 adapter    
USB-COM232-4A Four-port USB to serial RS-232 adapter    
USB-COM-4S Four-port USB to serial RS-422/485 adapter    
USB-COM-4SM Four-Port USB to Serial RS-232/422/485 adapter    
USB-COM-4SM Four-Port Serial Communications adapter for Universal Serial Bus    
USB-IIRO4-2SM Two-Port USB to Serial RS-232/422/485 adapter with 4 Electromechanical relays and 4 optically isolated inputs.    
ethernet eNET-232-1 (OBSOLETE) Single-Port Ethernet-to-Remote RS-232 Serial Interface Device    (OBSOLETE)
eNET-422-1 (OBSOLETE) Single-Port Ethernet-to-Remote RS-422 Serial Interface Device    (OBSOLETE)
PCMCIA PCM485 PCM485 PCMCIA RS-422/485 Serial Communications Card    please call
Watchdog WDG-SIO Watchdog Timer and RS422/485 Serial Communications Card    
WDG-2S Watchdog Timer and Dual RS422/RS485 Serial Communications Card    
ISA Bus COM422/485A
and ICOM 422/485A
Single-Port RS-422/485 Serial Communications Card (ICOM is isolated)
COM-1S Single-Port RS-232/422/485 Serial Communications Card    
COM-2S Two-Port, RS-232/422/485 Serial Communications Card    
ICOM-2S Optically-Isolated, Dual-Port RS-422 and RS-485 Serial Communications Card    
and COM485/4
Four-Port Serial Communications Cards    
COM485/8 Eight-Port Serial Communications Card      



ANDROID-232 RS-232 Port for your Android Device      
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.

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Eastern Canada - Markham, Ontario

Tel:1.800.465.0164 or 1.905.513.7027