KANDA STK300, Руководство пользователя

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Page 27
The on-board Watchdog Timer (WDT) can be enabled or disabled. If it is enabled a prescaler can
be applied to lengthen the WDT time-out period. The minimum time-out period is 16 mS and the
maximum is 2048 mS. If emulation is required it is recommended that the WDT is disabled.
SRAM
External SRAM can be used with some AVR devices - see device data sheets for details. The
external SRAM enable bit must be set (SRE bit in MCUCR Register). Some operations e.g.
memory mapped LCD driving require a longer clock pulse. This can be achieved by inserting a
wait state.
Stack Pointer
This sets the position in memory at which the stack will start, in hexadecimal. The default value
given is the top of internal SRAM in the device selected, as the stack grows downwards in AVR
devices. Change this value if you require the stack elsewhere in internal or external SRAM. By
default, if the box is clear, this value is set to be zero.
Note : AT90S1200 devices have a hardware stack so this option is disabled if this device is
selected.
External SRAM and SRAM wait state are enabled with the two check boxes on the left-hand
side. These options enable external SRAM access and slow the Read/Write pulses if required.
Output Type
The type of code output can be selected. There is a choice of assembler output or C Code.
There are some differences between IAR and Atmel assemblers - include file paths etc. so select
the correct assembly language output type.
Next Button
This button will move you to the next page selected in the Peripherals list. If no peripherals are
selected, a minimal template is generated.
Note: If at any time you press a back button to get to this screen, the device select list
WILL be disabled i.e. You can not change device once you leave this screen.