25
AT94KAL Series FPSLIC
Rev. 1138G–FPSLI–11/03
A Side
The A side is partitioned into Program memory and Data memory:
•
Program memory is 16-bit words.
•
Program memory address $0000 always starts in the highest two SRAMs (n - 1, n)
[SRAMn - 1 (low byte) and SRAMn (high byte)] (SRAM labels are for layout, the
addressing scheme is transparent to the AVR PC).
•
System configuration determines the higher addresses for program memory:
– SCR bits 41 = 0 : 40 = 0, program memory extended from $2800 - $3FFF
– SCR bits 41 = 0 : 40 = 1, program memory extended from $2800 - $37FF
– SCR bits 41 = 1 : 40 = 0, program memory extended from $2800 - $2FFF
– SCR bits 41 = 1 : 40 = 1, no extra program memory
•
Extended program memory is always lost to extended data memory from SRAM2/3 down
to SRAM6/7, see Table 5.
•
Data memory is 8-bit words.
•
Data memory address $0000 always starts in SRAM0 (SRAM labels are for layout, the
addressing scheme is transparent to AVR data read/write).
•
System configuration determines the higher address for data memory:
–
SCR bits 41 = 0 : 40 = 0, no extra data memory
–
SCR bits 41 = 0 : 40 = 1, data memory extended from $1000 - $1FFF
–
SCR bits 41 = 1 : 40 = 0, data memory extended from $1000 - $2FFF
–
SCR bits 41 = 1 : 40 = 1, data memory extended from $1000 - $3FFF
•
Extended data memory is always lost to extended program memory from SRAM7 up to
SRAM2 in 2 x SRAM blocks, see Table 6.
Table 5.
AVR Program Decode for SRAM 2:7 (16K16)
Address Range
SRAM
Comments
$3FFF - $3800
$3FFF - $3800
02
03
CR41:40 = 00
$37FF - $3000
$37FF - $3000
04
05
CR41:40 = 00,01
$2FFF - $2800
$2FFF - $2800
06
07
CR41:40 = 00,01,10
$27FF - $2000
$27FF - $2000
$1FFF - $1800
$1FFF - $1800
$17FF - $1000
$17FF - $1000
$0FFF - $0800
$0FFF - $0800
$07FF - $0000
$07FF - $0000
08
09
10
11
12
13
14
15
16
n = 17
AVR Program Read-only
AVR Program Read-only
AVR Program Read-only
AVR Program Read-only
AVR Program Read-only
AVR Program Read-only
AVR Program Read-only
AVR Program Read-only
AVR Program Read-only
AVR Program Read-only