Datasheet

340
XMEGA B [DATASHEET]
8291B–AVR–01/2013
26.15.7 TEMP – Temporary register
 Bit 7:0 – TEMP[7:0]: Temporary bits
This register is used when reading 16-bit registers in the ADC controller. The high byte of the 16-bit register is stored
here when the low byte is read by the CPU. This register can also be read and written from the user software.
For more details on 16-bit register access, refer to “Accessing 16-bit Registers” on page 11.
26.15.8 SAMPCTRL – Sampling time control register
 Bit 7:6 – Reserved
These bits are unused and reserved for future use. For compatibility with future devices, always write these bits to zero
when this register is written.
 Bit 5:0 – SAMPVAL[5:0]: sampling time control register
These bits control the ADC sampling time in number of half ADC prescaled clock cycles (depends of ADC_PRESCALER
value), thus controlling the ADC input impedance. Sampling time is set according to the formula:
Sampling time = (SAMPVAL + 1)*(Clk
ADC
/2)
26.15.9 CALL – Calibration Value register Low
The CALL and CALH register pair hold the 12-bit calibration value. The ADC is calibrated during production
programming, and the calibration value must be read from the signature row and written to the CAL register from
software.
 Bit 7:0 – CAL[7:0]: ADC Calibration value
These are the eight lsbs of the 12-bit CAL value.
26.15.10CALH – Calibration Value register High
 Bit 3:0 – CAL[11:8]: Calibration value
These are the four msbs of the 12-bit CAL value.
Bit 76543210
+0x07 TEMP[7:0]
Read/Write R/W R/W R/W R/W R/W R/W R/W R/W
Initial Value 0 0000000
Bit 76543210
+0x08
– – SAMPVAL[5:0]
Read/Write R R R/W R/W R/W R/W R/W R/W
Initial Value 00000000
Bit 76543210
+0x0C CAL[7:0]
Read/Write R/W R/W R/W R/W R/W R/W R/W R/W
Initial Value 0 0 0 0 0 0 0 0
Bit 76543210
+0x0D
– – – – CAL[11:8]
Read/Write R/W R/W R/W R/W R/W R/W R/W R/W
Initial Value 0 0 0 0 0 0 0 0