Peripheral Simulation

For Atmel AT91SAM7A3 — Debug Unit

Simulation support for this peripheral or feature is comprised of:

• Dialog boxes which display and allow you to change peripheral configuration.

These simulation capabilities are described below.

Debug Unit Dialog

The Debug Unit Dialog configures built-in Debug Unit.

Control

• DBGU_CR (Debug Control Register) displays the combined control information for the following:
• RXEN (Receiver Enable) enables the receiver.
• TXEN (Transmitter Enable) enables the transmitter.
• RXDIS (Receiver Disable) disables the receiver.
• TXDIS (Transmitter Disable) disables the transmitter.
• RSTRX (Reset Receiver) resets the receiver.
• RSTTX (Reset Transmitter) resets the transmitter.
• RSTSTA (Reset Status Bits) resets the Parity Error (PARE), Framing Error (FRAME), Overrun Error (OVRE) and Break Received (RXBRK) status bits.

Mode

• DBGU_MR (Mode Register) contains the following Mode settings:
• CHMODE (Channel Mode) selects normal, loopback, echo or remote loopback pin configurations.
• PAR (Parity Type) selects the generation of even, odd or no parity bits, mark or space, or multi-drop mode.

Baudrate Generator

• DBGU_BRGR (Baud Rate Generator Register) holds the following values:
• CD (Clock Divisor) contains the value divided into the clock that determines the baud rate.
• Baudrate displays the calculated baud rate.

Receiver & Transmitter

• DBGU_RHR (Receiver Holding Register) contains the RXCHR character.
• RXCHR (Received Character) holds the last character received.
• DBGU_THR (Transmitter Holding Register) contains the TXCHR character.
• TXCHR (Character to be Transmitted) holds the next character to be transmitted.

Interrupt Mask & Status

• DBGU_IMR (Interrupt Mask Register) holds the masking bits for all of the internal peripheral interrupts.
• DBGU_SR (Channel Status Register) hold the following composite status:
• PARE (Parity Error) set if the controller detects at least 1 false parity bit since the last Reset Status Bits command (RSTSTA).
• FRAME (Framing Error) set if the controller detects a framing error since the last Reset Status Bits command (RSTSTA).
• OVRE (Overrun Error) set if the controller detects an overrun condition since the last Reset Status Bits command (RSTSTA).
• ENDTX (End of Transmitter Transfer) is set if the End of Transmitter signal is active.
• ENDRX (End of Receiver Transfer) is set if the End of Receiver signal is active.
• TXRDY (Transmitter Ready) set if the transmit hold register (DBGU_THR) is empty and there is no break request pending.
• RXRDY (Receiver Ready) set when the USART receives at least 1 character and the receiver hold register (DBGU_RHR) is not empty.
• COMMTX (Debug Communication Channel Write Status) is set if the Debug Communication Channel Write signal is active.
• COMMRX (Debug Communication Channel Read Status) is set if the Debug Communication Channel Read signal is active.
• RXBUFF (Receive Buffer Full) is set if the Buffer Full signal from the PDC is active.
• TXBUFF (Transmit Buffer Full) is set if the Buffer Empty signal from the PDC is active.
• TXEMPTY (Transmitter Empty) set if there are no characters in the transmitter hold register.

Chip ID

• DBGU_CDIR (Chip ID Register) contains the chip identification information: processor type, NV memory size, Internal RAM size, NV memory type and chip architecture.
• EXT (Extension Flag) is set when an extended chip ID exists.

Chip ID Extension

• DBGU_EXID (Extension ID) displays the chip extension ID.

Force NTRST

• DBGU_FNR (Force NTRST Register) hold the following bit setting:
• FNTRST (Force NTRST) is set to hols the NTRST of the ARM processor's TAP controller low. If reset, the TAP controller is driven by the ICE_NRESET signal.