mc68hc908bd48 Freescale Semiconductor, Inc, mc68hc908bd48 Datasheet - Page 174

• Manufacturer Part Number: mc68hc908bd48
• Description: M68hc08 Microcontrollers Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

Universal Serial Bus Module (USB)
13.5.6 USB Control Register 2 (UCR2)
Data Sheet
174
Address:
RSTIFR — Reset Interrupt Flag Clear
TX1STR — TX1ST Clear
PULLEN — Pullup Enable on D–
SUSPND — USB Suspend
Reset:
Read:
Write: RSTIFR
Writing a logic "1" to this bit clears the RSTIFR flag. Writing a "0" has
no effect. Reset clears this bit.
Writing a logic "1" to this bit clears the TX1STR flag. Writing a "0" has
no effect. Reset clears this bit.
This bit is set to enable the internal 1.5kΩ pullup resister connected
between the USB D– line and 3.3V. Reset clears this bit.
If the 3ms constant idle state is detected on the USB bus, user
software should set this bit to allow the USB module to enter suspend
mode. In the suspend mode, the clock to USB module will be stopped,
and other unnecessary analog circuitry will be powered down. When
a resume is detected (RESUMF = 1), user software must clear
SUSPND in the interrupt service routine.
1 = Writing 1 clears RSTIFR
0 = No effect
1 = Writing 1 clears TX1STR
0 = No effect
1 = Enable 1.5kΩ pullup resistor between D– and 3.3V
0 = Disable 1.5kΩ pullup resistor between D– and 3.3V
1 = Enable USB suspend mode
0 = Disable USB suspend mode
$002D
Bit 7
Universal Serial Bus Module (USB)
0
0
Figure 13-6. USB Control Register 2 (UCR2)
TX1STR
6
0
0
PULLEN SUSPND ENABLE2 ENABLE1 STALL2
5
0
4
0
3
0
MC68HC908BD48
Freescale Semiconductor
2
0
1
0
—
STALL1
Rev. 2.1
Bit 0
0