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2 Channel Serial I/O Module (SIO-102)

2 Channel Serial Module

  • 2 Channel serial RS-232C I/O PC/104 expansion module
  • Stack-Through, 16 bit
  • Based on industry norm 16C550 architecture
  • 2 independent high-speed serial ports with on-board RS-232C drivers
  • +5V only
  • 16C550 16 byte FIFOs
  • Supports all serial speeds between 75bps and 115,200bps

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The SIO-102 is a 2-channel Serial RS-232C Input-Output PC/104-16 Expansion Module with two 16C550 based programmable Serial Ports that work from +5V only.

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Based on the industry norm 16C550 architecture, the SIO-102 is a Stack-Through, 16-bit, PC/104 Board featuring two completely independent high-speed Serial Ports with on-board RS-232C Drivers/Receivers that work from +5V only. Featuring the 16C550's 16-byte FIFOs, each Serial Port is individually programmable for use at any serial speed between 75bps and 115,200bps.

Operating from +5V only, the SIO-102 is fully capable of operating in all modes supported by the 16C550. Each Channel can be set to generate an Interrupt selectable by individual Jumpers from any available interrupt in the system.

Each channel takes only 8 consecutive I/O Address spaces and the base address of each can be located on any "0" or "8" boundary within the total I/O Address Space between 0000H and 07F8H (the I/O addresses shown in hexadecimal notation):

IO Address Space: 0000H to 0007H up to and including 07F8H (to 07FFH)
Interrupts: IRQ 3, 4, 5, 6, 7, 9, 10, 11, 12, 14 or 15

The I/O Address Space for each port is set by an on-board 8-position switch according to the Address List attached hereto. The Interrupt is selected individually for each Port by on-board Jumpers.

The Default Factory Settings for the two Ports are:
Port 1:
I/O Address:
03E8H (corresponds to the I/O Address of COM3)
IRQ 15
Port 2:
I/O Address:
02E8H (corresponds to the I/O Address of COM4)

Click HERE to get the Address Switch settings for the Total 000H - 7FFFH I/O Address Space

Serial Connectors
Each Port can be used with either the on-board DB-9, Male connector, or with the on-board 2*5 pin Header, for extended cabling. Note that, as these two connectors are connected "in parallel", only one of these should be used per Port. Note also that pin number 10 in the header is connected to +5V, allowing limited power supply of off-board units like, for instance IPS's TS-110 Serial Touch Screen Controller, through the 10-wire ribbon cable. Note also that this pin is not available when using the DB-9 Male serial connector.

There are no drivers needed, as the two ports are based on the architecture of the Industry Standard Serial Input-Output chip - the 16C550. Any serial port driver developed for use with the standard serial ports in the PC will work with these port, and, as an example, the drivers that come with all versions of Windows will work optimally with these ports. The interrupt outputs are high impedance when not active, allowing full sharing of any attached interrupt. Note that this will require a software driver written to allow for such sharing of interrupts!

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Board Outline

View Entire Document
PDF (454 KB)
Address Switch Settings
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