Atmel SAM4S Xplained Pro Starter and Evaluation Kit ATSAM4S-XPRO ATSAM4S-XPRO Fiche De Données
Codes de produits
ATSAM4S-XPRO
SAM4S Series [DATASHEET]
Atmel-11100G-ATARM-SAM4S-Datasheet_27-May-14
374
21.3.3 Entering Programming Mode
The following algorithm puts the device in Parallel Programming Mode:
Apply the supplies as described in
.
Apply XIN clock within T
POR_RESET
if an external clock is available.
Wait for T
POR_RESET
Start a read or write handshaking.
Note:
After reset, the device is clocked by the internal RC oscillator. Before clearing RDY signal, if an external clock ( > 32
kHz) is connected to XIN, then the device switches on the external clock. Else, XIN input is not considered. A higher
frequency on XIN speeds up the programmer handshake.
21.3.4 Programmer Handshaking
An handshake is defined for read and write operations. When the device is ready to start a new operation (RDY
signal set), the programmer starts the handshake by clearing the NCMD signal. The handshaking is achieved once
NCMD signal is high and RDY is high.
21.3.4.1 Write Handshaking
For details on the write handshaking sequence, refer to
and
.
Figure 21-2.
Parallel Programming Timing, Write Sequence
0x0025
GGPB
Get General Purpose NVM bit
0x0054
SSE
Set Security Bit
0x0035
GSE
Get Security Bit
0x001F
WRAM
Write Memory
0x001E
GVE
Get Version
Table 21-3.
Command Bit Coding (Continued)
DATA[15:0]
Symbol
Command Executed
NCMD
RDY
NOE
NVALID
DATA[15:0]
MODE[3:0]
1
2
3
4
5