Industry standard ports

Hardware checkpoint 3.1

Provide industry standard ports for alternative input and output devices.

Rationale

A user with severe mobility impairments cannot use the standard keyboard or mouse. The system needs to provide an industry standard port, so the user can attach a switch or other alternate input device to replace the keyboard. The system will regard this device as its keyboard, and the user will be able to input any valid keystroke combination available from the regular keyboard.

A blind or vision impaired user who cannot use the standard display may need to attach a hardware speech synthesis device or a Braille display. Such alternative output devices can also be attached using an industry standard port.

Development techniques

This checkpoint applies only to desktop and portable computers.

The following techniques are the minimum required to meet Checkpoint 3.1 from the IBM Hardware Accessibility Checklist:

Provide an industry standard serial, parallel, or USB port which can be used to attach alternate input and output devices.
If attaching an external display is supported, provide a standard display connector. A standard video connector or I/O slot that allows connection of a video control card would satisfy this requirement.
When products provide auditory output, provide the audio signal at a standard signal level through an industry standard connector that will allow for private listening. This provision applies only to voice output.

Testing techniques

Test the hardware to ensure that it complies with accessibility requirements.

Tools

A sound level meter.

Techniques

*One or more of the following techniques are **required** to verify this checkpoint:*
	Action	Result
1	Verify the system has an industry standard port. e.g. RS-232, PCMCIA, USB Visually and by verifying specifications.	Pass: System has at least one industry standard port Fail: System has no industry standard ports.
2	If the system supports attaching an external display, verify there is a standard display connector. Visually and by verifying specifications.	Pass: A standard video connector is present or an I/O slot that allows connection of a video control card is present. Fail: A standard video connector is not present, nor is an I/O slot that allows connection of a video control card present.
3	When a system provides auditory output verify that the audio signal is provided at a standard signal level, through a standard connection. Check the output of the auditory channel output with a sound level meter.	Pass: Audio signal is approximately 65dB which is the level of normal speech. Audio signal is provided though a standard connection. Examples of common plugs on headsets include those that fit 2.5 mm jacks (such as those in most cellular phones) and 3.5 mm plugs (such as those in most portable stereos). Fail: Audio signal is greater than 70dBs or less than 60dBs A standard headset will not attach to the connector.

Last updated February 22, 2008.

Checklist