Datasheet

352
8331B–AVR–03/12
Atmel AVR XMEGA AU
Note: 1. Entire available data space used.
• Bit 1:0 – MODE[1:0]: Chip Select Mode
These bits select the Chip Select Mode and decide what type of interface is used for the external
memory or peripheral according to Table 27-22 on page 352.
Note: 1. SDRAM can only be selected for CS3
Table 27-21. Address size encoding
ASIZE[4:0] Group Configuration Address Size Address Lines Compared
00000 256B 256 bytes ADDR[23:8]
00001 512B 512 bytes ADDR[23:9]
00010 1K 1KB ADDR[23:10]
00011 2K 2KB ADDR[23:11]
00100 4K 4KB ADDR[23:12]
00101 8K 8KB ADDR[23:13]
00110 16K 16KB ADDR[23:14
00111 32K 32KB ADDR[23:15]
01000 64K 64KB ADDR[23:16]
01001 128K 128KB ADDR[23:17]
01010 256K 256KB ADDR[23:18]
01011 512K 512KB ADDR[23:19]
01100 1M 1MB ADDR[23:20]
01101 2M 2MB ADDR[23:21]
01110 4M 4MB ADDR[23:22]
01111 8M 8MB ADDR[23]
10000 16M 16MB
(1)
–
Other – – Reserved
Table 27-22. Chip Select Mode selection
MODE[1:0] Group Configuration Description
00 DISABLE Chip select disabled
01 SRAM Enable chip select for SRAM
10 LPC Enable chip select for SRAM LPC
11 SDRAM Enable chip select for SDRAM
(1)