AT91RM3400-DK Atmel, AT91RM3400-DK Datasheet - Page 46

• Manufacturer Part Number: AT91RM3400-DK
• Description: KIT DEV FOR AT91RM3400
• Manufacturer: Atmel
• Series: AT91SAM Smart ARMr
• Type: MCUr

Specifications of AT91RM3400-DK

• Contents: Evaluation Board, Software and Documentation
• Processor To Be Evaluated: AT91RM3400
• Data Bus Width: 32 bit
• Interface Type: RS-232, USB
• For Use With/related Products: AT91RM3400
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

Valid Image
Detection
Figure 11. LDR Opcode
Figure 12. B Opcode
Example
46
AT91RM3400
31
31
1
1
1
1
1
1
28 27
28 27
0
0
1
1
The Bootloader software looks for a valid application by analyzing the first 32 bytes corre-
sponding to the ARM exception vectors. These bytes must implement ARM instructions for
either branch or load PC with PC relative addressing. The sixth vector, at offset 0x18, contains
the size of the image to download and the DataFlash parameters.
The user must replace this vector with his own vector.
Unconditional instruction: 0xE for bits 31 to 28
Load PC with PC relative addressing instruction:
An example of valid vectors:
In download mode (DataFlash, EEPROM or 8-bit memory in device with EBI integrated), the
size of the image to load into SRAM is contained in the location of the sixth ARM vector. Thus
the user must replace this vector by the correct vector for his application.
1
0
–
–
–
–
–
00
004
08
0c
10
14
18
1c
1
I
Rn = Rd = PC = 0xF
I==1
P==1
U offset added (U==1) or subtracted (U==0)
W==1
24 23
24 23
P
0
ea00000b
e59ff014
e59ff014
e59ff014
e59ff014
00001234
e51fff20
e51fff20
U
1
W 0
20 19
B
LDR
LDR
LDR
LDR
LDR
LDR
LDR
Rn
16 15
Offset (24 bits)
0x2c
PC, [PC,20]
PC, [PC,20]
PC, [PC,20]
PC, [PC,20]
PC, [PC,20]
PC, [PC,-0xf20]
PC, [PC,-0xf20]
Rd
12 11
<- Code size = 4660 bytes
0
0
1790A–ATARM–11/03