usb1 Device USB2 Host

Double post to Yahoo LPC2000
tech.groups.yahoo.com/.../37995

"the USB2 as a Host and the USB1 as a Device but in this two USB have one signal connetet together it is the P1.30, in USB 2 is directly connected at the micro processor in the USB1 it is connected with one resistor R71 is correct ?"

VBUS pin of the host connector - supplied 5V from LM3256 - OK
VBUS pin of the device connector - supplied 5V over R71 (4k7) - not good.

The problems of this circuit are twofold
1) the board cannot detect attach to host on the VBUS pin of the device connector.
2) the board sources current to the VBUS pin of the device connector.
The source current doesn't make so much trouble because the resistor value is large enough, but obviously, violation of this USB spec (bold face). To fulfill the later half of this spec, VBUS detection is necessary.

"7.2.1 Classes of Devices (USB_20.pdf)
No device shall supply (source) current on VBUS at its upstream facing port at any time. From VBUS on its upstream facing port, a device may only draw (sink) current. They may not provide power to the pull-up resistor on D+/D- unless VBUS is present (see Section 7.1.5). When VBUS is removed, the device must remove power from the D+/D- pull-up resistor within 10 seconds."

LPC2388/2468/2478 have four options of USB port configuration. I have examined several development boards for these chips.
Not just KEIL, all board has some trouble in one or two options.



"The other question is the P2.9 in the errata sheet page 7, is correct the schematich in the MCB2300 board?"

What do you mean?
The errata describes about error on U1CONNECT function. As it suggests, the error is patched on the firmware.
If you are talking about the "external 1.5 KΩ resistor", it's R3, switched by Q1 on the MCB2300-v47 schematic.

"USB.2: U1CONNECT signal is not functional (errata.lpc2388.pdf p7)
U1CONNECT Signal (alternate function of P2.9) is part of the SoftConnect USB feature, which is used to switch an external 1.5 KΩ resistor under the software control."

Tsuneo

Double post to Yahoo LPC2000
tech.groups.yahoo.com/.../37995

"the USB2 as a Host and the USB1 as a Device but in this two USB have one signal connetet together it is the P1.30, in USB 2 is directly connected at the micro processor in the USB1 it is connected with one resistor R71 is correct ?"

VBUS pin of the host connector - supplied 5V from LM3256 - OK
VBUS pin of the device connector - supplied 5V over R71 (4k7) - not good.

The problems of this circuit are twofold
1) the board cannot detect attach to host on the VBUS pin of the device connector.
2) the board sources current to the VBUS pin of the device connector.
The source current doesn't make so much trouble because the resistor value is large enough, but obviously, violation of this USB spec (bold face). To fulfill the later half of this spec, VBUS detection is necessary.

"7.2.1 Classes of Devices (USB_20.pdf)
No device shall supply (source) current on VBUS at its upstream facing port at any time. From VBUS on its upstream facing port, a device may only draw (sink) current. They may not provide power to the pull-up resistor on D+/D- unless VBUS is present (see Section 7.1.5). When VBUS is removed, the device must remove power from the D+/D- pull-up resistor within 10 seconds."

LPC2388/2468/2478 have four options of USB port configuration. I have examined several development boards for these chips.
Not just KEIL, all board has some trouble in one or two options.



"The other question is the P2.9 in the errata sheet page 7, is correct the schematich in the MCB2300 board?"

What do you mean?
The errata describes about error on U1CONNECT function. As it suggests, the error is patched on the firmware.
If you are talking about the "external 1.5 KΩ resistor", it's R3, switched by Q1 on the MCB2300-v47 schematic.

"USB.2: U1CONNECT signal is not functional (errata.lpc2388.pdf p7)
U1CONNECT Signal (alternate function of P2.9) is part of the SoftConnect USB feature, which is used to switch an external 1.5 KΩ resistor under the software control."

Tsuneo