42
8331B–AVR–03/12
Atmel AVR XMEGA AU
4.17.18
USBCAL1 – USB Pad Calibration register 1
• Bit 7:0 – USBCAL1[7:0]: USB Pad Calibration Register 1
This byte contains byte 1 of the USB pin calibration data, and must be loaded into the USB
CALH register.
4.17.19
RCOSC48M – USB RCOSC Calibration
• Bit 7:0 – RCOSC48M[7:0]: 48MHz RSCOSC Calibration
This byte contains a 48MHz calibration value for the internal 32MHz oscillator. When this cali-
bration value is written to calibration register B for the 32MHz DFLL, the oscillator is calibrated to
48MHz to enable full-speed USB operation from internal oscillator.
Note:
The COMP2 and COMP1 registers inside the DFLL32M must be set to B71B.
4.17.20
ADCACAL0 – ADCA Calibration register 0
ADCACAL0 and ADCACAL1 contain the calibration value for the analog to digital converter A
(ADCA). Calibration is done during production test of the device. The calibration bytes are not
loaded automatically into the ADC calibration registers, so this must be done from software.
• Bit 7:0 – ADCACAL0[7:0]: ADCA Calibration Byte 0
This byte contains byte 0 of the ADCA calibration data, and must be loaded into the ADCA CALL
register.
4.17.21
ADCACAL1 – ADCA Calibration register 1
Bit
7
6
5
4
3
2
1
0
+0x1B
USBCAL1[7:0]
USBCAL1
Read/Write
R
R
R
R
R
R
R
R
Initial Value
x
x
x
x
x
x
x
x
Bit
7
6
5
4
3
2
1
0
+0x1C
RCOSC48M[7:0]
RCOSC48M
Read/Write
R
R
R
R
R
R
R
R
Initial Value
x
x
x
x
x
x
x
x
Bit
7
6
5
4
3
2
1
0
+0x20
ADCACAL0[7:0]
ADCACAL0
Read/Write
R
R
R
R
R
R
R
R
Initial Value
x
x
x
x
x
x
x
x
Bit
7
6
5
4
3
2
1
0
+0x21
ADCACAL1[7:0]
ADCACAL1
Read/Write
R
R
R
R
R
R
R
R
Initial Value
x
x
x
x
x
x
x
x
