SAM9XE512 Atmel Corporation, SAM9XE512 Datasheet - Page 264

• Manufacturer Part Number: SAM9XE512
• Manufacturer: Atmel Corporation

Specifications of SAM9XE512

• Flash (kbytes): 512 Kbytes
• Pin Count: 217
• Max. Operating Frequency: 180 MHz
• Cpu: ARM926
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 96
• Ext Interrupts: 96
• Usb Transceiver: 3
• Usb Speed: Full Speed
• Usb Interface: Host, Device
• Spi: 2
• Twi (i2c): 2
• Uart: 6
• Ssc: 1
• Ethernet: 1
• Sd / Emmc: 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: Yes
• Adc Channels: 4
• Adc Resolution (bits): 10
• Adc Speed (ksps): 312
• Resistive Touch Screen: No
• Temp. Sensor: No
• Crypto Engine: No
• Sram (kbytes): 32
• Self Program Memory: NO
• External Bus Interface: 1
• Dram Memory: sdram
• Nand Interface: Yes
• Picopower: No
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 1.8/3.3
• Operating Voltage (vcc): 1.65 to 1.95
• Fpu: No
• Mpu / Mmu: No / Yes
• Timers: 6
• Output Compare Channels: 6
• Input Capture Channels: 6
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: No

Debug in depth
C.8
C.8.1
C.8.2
C-24
Behavior of the program counter during debug
Breakpoints
Watchpoints
you can replace the final branch with a subtract, with the PC as the destination (
The debugger must keep track of what happens to the PC, so that you can force the
ARM9E-S to branch back to the place at which program flow was interrupted by debug.
Program flow can be interrupted by any of the following:
•
•
•
•
•
Entry to debug state from a breakpointed instruction advances the PC by 16 bytes in
ARM state, or 8 bytes in Thumb state. Each instruction executed in debug state
advances the PC by one address (4 bytes). The normal way to exit from debug state after
a breakpoint is to remove the breakpoint and branch back to the previously breakpointed
address.
For example, if the ARM9E-S entered debug state from a breakpoint set on a given
address and two debug speed instructions were executed, a branch of seven addresses
must occur (four for debug entry, plus two for the instructions, plus one for the final
branch). The following sequence shows ARM instructions scanned into scan chain 1.
This is the Most Significant Bit (MSB) first, so the first digit represents the value to be
scanned into the SYSSPEED bit, followed by the instruction.
0 EAFFFFF9 ; B -7 addresses (two’s complement)
1 E1A00000 ; NOP (MOV R0, R0), SYSSPEED bit is set
After the ARM9E-S enters debug state, it must execute a minimum of two instructions
before the branch, although these can both be NOPs (
PC, PC, #28
To return to program execution after entry to debug state from a watchpoint, use the
same procedure described in Breakpoints.
Debug entry adds four addresses to the PC, and every instruction adds one address. The
difference from breakpoint is that the instruction that caused the watchpoint has
executed, and the program must return to the next instruction.
a breakpoint
a watchpoint
a watchpoint when another exception occurs
a debug request
a system speed access.
Copyright © 2000 ARM Limited. All rights reserved.
in the above example).
MOV R0, R0
). For small branches,
ARM DDI 0165B
SUB