Datasheet

130
SAM7S Series [DATASHEET]
6175M–ATARM–26-Oct-12
20.2.5 Device Operations
Several commands on the Flash memory are available. These commands are summarized in Table 20-3 on page
126. Each command is driven by the programmer through the parallel interface running several read/write hand-
shaking sequences.
When a new command is executed, the previous one is automatically achieved. Thus, chaining a read command
after a write automatically flushes the load buffer in the Flash.
In the following tables, 21-6 through 21-18
• DATA[15:0] pertains to SAM7S512/256/128/64/321/161
• DATA[7:0] pertains to SAM7S32/16
20.2.5.1 Flash Read Command
This command is used to read the contents of the Flash memory. The read command can start at any valid
address in the memory plane and is optimized for consecutive reads. Read handshaking can be chained; an inter-
nal address buffer is automatically increased.
Table 20-6. Read Command
Step Handshake Sequence MODE[3:0] DATA[15:0]
1 Write handshaking CMDE READ
2 Write handshaking ADDR0 Memory Address LSB
3 Write handshaking ADDR1 Memory Address
4 Read handshaking DATA *Memory Address++
5 Read handshaking DATA *Memory Address++
... ... ... ...
n Write handshaking ADDR0 Memory Address LSB
n+1 Write handshaking ADDR1 Memory Address
n+2 Read handshaking DATA *Memory Address++
n+3 Read handshaking DATA *Memory Address++
... ... ... ...
Table 20-7. Read Command
Step Handshake Sequence MODE[3:0] DATA[7:0]
1 Write handshaking CMDE READ
2 Write handshaking ADDR0 Memory Address LSB
3 Write handshaking ADDR1 Memory Address
4 Write handshaking ADDR2 Memory Address
5 Write handshaking ADDR3 Memory Address
6 Read handshaking DATA *Memory Address++
7 Read handshaking DATA *Memory Address++
... ... ... ...
n Write handshaking ADDR0 Memory Address LSB
n+1 Write handshaking ADDR1 Memory Address