AT83EC5123 ATMEL Corporation, AT83EC5123 Datasheet - Page 29

• Manufacturer Part Number: AT83EC5123
• Description: (AT8xx512x) Smart Card Reader ICs
• Manufacturer: ATMEL Corporation

Figure 12. Oscillator Block Diagram
CPU and Peripheral Clock
4202B–SCR–07/03
XTAL2
XTAL1
PCON.1
PD
CK_XTAL1
Two clocks sources are available for CPU and peripherals:
These clock sources are adapted by the PR1 prescaler to generate the CPU core
CK_CPU and the peripheral clocks:
PLLCON.1
PLL 96
PLLEN
MHz
–
–
–
–
–
–
–
–
Crystal oscillator on XTAL1 and XTAL2 pins and a 96 MHz PLL (Set by SFR
to this value).
External 48 MHz clock on XTAL1 pin
CK_IDLE for alternate card and peripherals registers access
CK_T0 for Timer 0
CK_T1 for Timer 1
CK_SI for the UART
CK_WD for the Watchdog
CK_SPI for SPI
CK_XTAL1
CK_PLL
CK_PLL
XTSCS
EXT48
CKSEL.0
CKS
1/2
0
1
PLLCON.2
SCICLK.7
DCCKPS.3:0
CKRL.3:0
Periph = T0, T1, SI, WD or SPI
PR4
PR1
CK_XTAL1
CK_PLL
CK_XTAL1
CKCON0.X or
PeriphX2
CKCON1.0
CKCON.0
0
1
0
1
0
1
X2
0
1
CK_USB
CK_IDLE
SCICLK5:0
PR2
CKCON0.0
SCSR3:2
PCON.0
PR3
AT8xC5122/23
IDL
X2
1
0
CK_Periph
CK_IDLE
CK_ISO
CK_IDLE
CK_CPU
Peripherals
Converter
CK_T0
CK_T1
CK_SI
CK_WD
CK_SPI
Alt Card
DC/DC
SCIB
CPU
USB
29