Apparatus for detecting correct insertion of a PC card in an information processing system

• US 5,802,328 A
• Filed: 12/02/1996
• Issued: 09/01/1998
• Est. Priority Date: 05/30/1996
• Status: Expired due to Term

• Current Assignee: Renesas Electronics Corporation
• Original Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Inventors: Yoshimura, Yoshimasa
• Primary Examiner(s): Ray, Gopal C.
• Application Number:
  US08/759,000
• Time in Patent Office: 638 Days
• Field of Search: 395/282, 395/283, 395/309, 439/59, 439/62, 439/377, 307/38, 307/147, 361/683
• US Class Current: 710/301
• CPC Class Codes: G06F 13/4081 Live connection to bus, e.g. hot-plugging current or voltage limitation during live insertion H02H9/004
• CPC Class Codes: H05K 7/1455 Coding for prevention of wrong insertion
• CPC Class Codes: H05K 7/1459 Circuit configuration, e.g. routing signals
• CPC Class Codes: Y02D 10/00 Energy efficient computing, e.g. low power processors, power management or thermal management

Abstract

The PC card system device including a PC card in conformity with the PC card standard and an information processing device which the PC card is to be connected, comprises a card connector provided in the PC card, a device connector, provided in the information processing device, a connection state detector for detecting the connection state of the PC card according to the signal level of at least one contact of the device connector, and an interface controller for controlling the signal transfer from the device connector according to the determination of the connection state detector. The interface controller prohibits any signal transfer from the device connector if the connection state detector determines that the PC card is incorrectly connected to the information processing device.

Claims

1. A PC card system device comprising a PC card in conformity with the PCMCIA/JEIDA PC card standard and an information processing device to which said PC card is to be connected, further comprising:

a card connector means, provided in said PC card, for connecting said PC card to said information processing device;

a device connector means, provided in said information processing device, in conformity with said PC card standard, for connecting said card connector means of said PC card;

a connection state detecting means for detecting the connection state of said PC card according to the signal level of at least one contact of said device connector means; and

an interface control means for controlling the signal transfer from said device connector means according to the determination of said connection state detecting means,

said interface control means prohibiting any signal transfer from said device connector means if said connection state detecting means determines that said PC card is incorrectly connected to said information processing device.

2. The PC card system device of claim 1 wherein either the seventeenth contact or fifty-first contact of said device connector means, referred to as the Vcc1 contact, is connected to the power supply of said information processing device and the other contact, referred to as the Vcc2, is connected to the power supply of said information processing device through a first switch means and to a pull-down resistor, and wherein said interface control means turns on said first switch means only when said connection state detecting means determines that said PC card is properly connected.

3. The PC card system device of claim 2 wherein said connection state detecting means determines that said PC card is incorrectly connected when the Vcc2 contact of said device connector means is "L", and that said PC card is properly connected when the Vcc2 contact of said device connector means is "H".

4. The PC card system device of claim 2 further comprising a second switch means connected between said Vcc2 contact of said device connector means and said pull-down resistor, said interface control means turning off said second switch means only when said connection state detecting means determines that said PC card is properly connected.

5. The PC card system devise of claim 4 further comprising:

a connection detecting means for determining whether or not said PC card is connected to said information processing device according to the signal level of at least one contact of said device connector means; and

a third switch means for controlling the supply of power from said information processing device to the contact Vcc1 of the device connector means and to said first switch means,

said connection detecting means turning on said third switch means to allow the power supply voltage to be applied to said contact Vcc1 and to said first switch means only when said connection detecting means determines that said PC card is connected to said information processing device.

6. The PC card system device of claim 5 wherein said connection detecting means determines whether or not said PC card is connected to said information processing device according to the signal levels of the second, thirty-third, thirty-sixth, and sixty-seventh terminals of said device connector means.

7. The PC card system device of claim 6 wherein the second, thirty-third, thirty-sixth, and sixty-seventh contacts of said device connector means are connected to pull-up resistors and wherein said connection detecting means determines that said PC card is not connected to said information processing device when said second, thirty-third, thirty-sixth, and sixty-seventh contacts are all at an "H" level and that said PC card is connected to said information processing device when both said second and said thirty-third contacts are at an "L" level or when both said thirty-sixth and said sixty-seventh contacts are at an "L" level.

8. The PC card system device of claim 5 further comprising a fourth switch means, placed between the power supply of said information processing device and the terminals of said device connection means for providing power to said PC card, for controlling the supply of power to said PC card,

said interface control means turning on said fourth switch means allowing the power voltage to be applied to said contacts of said device connector means only when said connection state detecting means determines that said PC card is properly connected to said information processing device.

9. The PC card system device of claim 8 wherein said connection state detecting means determines whether or not said PC card is connected to said information processing device according to the signal levels of the second, thirty-third, thirty-sixth, and sixty-seventh contacts of said device connector means.

10. The PC card system device of claim 9 wherein the second, thirty-third, thirty-sixth, and sixty-seventh contacts of said device connector means are connected to pull-up resistors and wherein said connection state detecting means determines that said PC card is not connected to said information processing device when said second, thirty-third, thirty-sixth, and sixty-seventh contacts are all at an "H" level.

11. The PC card system device of claim 10 wherein said connection state detecting means determines that said PC card is properly connected to said information processing device when both said thirty-sixth and said sixty-seventh contacts are at an "L" level.

12. The PC card system device of claim 10 wherein said connection state detecting means determines that said PC card is incorrectly connected to said information processing device when both said second and said thirty-third contacts are at an "L" level.

13. The PC card system device of claim 4 further comprising a fourth switch means which controls the supply of power from said information processing device to said first switch means and to the contact Vcc1 of said device connector means,

said interface control means turning on said fourth switch means and allowing the power voltage to be applied to said first switch means and to the contact Vcc1 of said device connector means only when said connection state detecting means determines that said PC card is properly connected to said information processing device.

14. The PC card system device of claim 1 further comprising:

a connection detecting means for determining whether or not said PC card is connected to said information processing device according to the signal level of at least one terminal of said device connector means; and

a third switch means, placed between the power supply of said information processing device and the terminals of said device connector means for providing power to said PC card, for controlling the supply of power to said PC card,

said connection detecting means turning on said third switch means only when said connection detecting means determines that said PC card is connected to said information processing device, allowing the power voltage to be applied to said terminals of said device connector means.