at89c5131 ATMEL Corporation, at89c5131 Datasheet - Page 136

• Manufacturer Part Number: at89c5131
• Description: 8-bit Flash Microcontroller With Full Speed Usb Device At89c5131
• Manufacturer: ATMEL Corporation

USB Registers
134
AT89C5131
Table 90. USBCON Register
USBCON (S:BCh)
USB Global Control Register
Reset Value = 00h
Bit Number
USBE
7
7
6
5
4
3
2
1
0
SUSPCLK SDRMWUP
Bit Mnemonic
SDRMWUP
SUSPCLK
RMWUPE
DETACH
FADDEN
UPRSM
CONFG
6
USBE
5
Description
USB Enable
Set this bit to enable the USB controller.
Clear this bit to disable and reset the USB controller, to disable the USB
transceiver an to disable the USB controller clock inputs.
Suspend USB Clock
Set this bit to disable the 48 MHz clock input (Resume Detection is still
active).
Clear this bit to enable the 48 MHz clock input.
Send Remote Wake Up
Set this bit to force an external interrupt on the USB controller for Remote
Wake UP purpose.
An upstream resume is send only if the bit RMWUPE is set, all USB clocks
are enabled AND the USB bus was in SUSPEND state for at least 5 ms.
See UPRSM below.
This bit is cleared by software.
Detach Command
Set this bit to simulate a Detach on the USB line. The V
floating state.
Clear this bit to maintain V
Upstream Resume (read only)
This bit is set by hardware when SDRMWUP has been set and if RMWUPE
is enabled.
This bit is cleared by hardware after the upstream resume has been sent.
Remote Wake-Up Enable
Set this bit to enabled request an upstream resume signaling to the host.
Clear this bit otherwise.
Note: Do not set this bit if the host has not set the
DEVICE_REMOTE_WAKEUP feature for the device.
Configured
This bit will be set by the device firmware after a SET_CONFIGURATION
request with a non-zero value has been correctly processed.
It will be cleared by the device firmware when a SET_CONFIGURATION
request with a zero value is received. It is cleared by hardware on hardware
reset or when an USB reset is detected on the bus (SE0 state for at least 32
Full Speed bit times: typically 2.7 µs).
Function Address Enable
This bit will be set by the device firmware after a successful status phase of
a SET_ADDRESS transaction.
It will not be cleared afterwards by the device firmware. It is cleared by
hardware on hardware reset or when an USB reset is received (see above).
When this bit is cleared, the default function address is used (0).
DETACH
4
UPRSM
REF
3
at 3.3V.
RMWUPE
2
CONFG
1
REF
4136C–USB–04/05
pin is then in a
FADDEN
0