Rainbow-electronics ATmega128RFA1 Manual de usuario Pagina 447

  • Descarga
  • Añadir a mis manuales
  • Imprimir
  • Pagina
    / 524
  • Tabla de contenidos
  • MARCADORES
  • Valorado. / 5. Basado en revisión del cliente
Vista de pagina 446
447
8266A-MCU Wireless-12/09
ATmega128RFA1
29.5.3 Scanning the RSTON Pin
For the low-active reset output pin RSTON a boundary-scan cell as shown in Figure
29-6 below is inserted.
Figure 29-6. Boundary-scan Cell for Output Pins without Pull-up Function
0
1
0
1
EXTEST
To Next Cell
ShiftDR
From System Logic
From Previous
Cell
UpdateDRClockDR
LD0FF0
D Q D Q
G
29.6 Boundary-scan Related Register in I/O Memory
29.6.1 MCUCR – MCU Control Register
Bit 7 6 5 4 3 2 1 0
$35 ($55) JTD MCUCR
Read/Write RW
Initial Value 0
The MCU Control Register contains control bits for general Microcontroller Unit
functions.
Bit 7 – JTD - JTAG Interface Disable
When this bit is zero, the JTAG interface is enabled if the JTAGEN Fuse is
programmed. If this bit is one, the JTAG interface is disabled. In order to avoid
unintentional disabling or enabling of the JTAG interface, a timed sequence must be
followed when changing this bit: The application software must write this bit to the
desired value twice within four cycles to change its value. Note that this bit must not be
altered when using the On-chip Debug system.
29.6.2 MCUSR – MCU Status Register
Bit 7 6 5 4 3 2 1 0
$34 ($54) JTRF MCUSR
Read/Write RW
Initial Value 0
The MCU Status Register provides information on which reset source caused an MCU
reset.
Vista de pagina 446
1 2 ... 442 443 444 445 446 447 448 449 450 451 452 ... 523 524

Comentarios a estos manuales

Sin comentarios