attiny25v ATMEL Corporation, attiny25v Datasheet - Page 148

• Manufacturer Part Number: attiny25v
• Description: Microcontroller With 2/4/8k Bytes In-system Programmable Flash
• Manufacturer: ATMEL Corporation

19.6.3
148
ATtiny25/45/85
Reading Device Signature Imprint Table from Firmware
To read the Fuse High Byte (FHB), simply replace the address in the Z-pointer with 0x0003 and
repeat the procedure above. If successful, the contents of the destination register are as follows.
Refer to
To read the Fuse Extended Byte (FEB), replace the address in the Z-pointer with 0x0002 and
repeat the previous procedure. If successful, the contents of the destination register are as
follows.
Refer to
Byte.
To read the contents of the device signature imprint table, follow the below procedure:
See program example below.
Note:
If successful, the contents of the destination register are as described in section
ture Imprint Table” on page
Bit
Rd
Bit
Rd
Assembly Code Example
1. Load the Z-pointer with the table index.
2. Set RSIG and SPMEN bits in SPMCSR.
3. Issue an LPM instruction within three clock cycles.
4. Read table data from the LPM destination register.
DSIT_read:
; Uses Z-pointer as table index
ldi
ldi
; Preload SPMCSR bits into R16, then write to SPMCSR
ldi
out SPMCSR, r16
; Issue LPM. Table data will be returned into r17
lpm r17, Z
ret
1. See
Table 20-4 on page 152
Table 20-3 on page 152
ZH, 0
ZL, 1
r16, (1<<RSIG)|(1<<SPMEN)
“Code Examples” on page
FHB7
FEB7
7
7
FHB6
FEB6
(1)
6
6
153.
for detailed description and mapping of the Fuse High Byte.
FHB5
FEB5
for detailed description and mapping of the Fuse Extended
5
5
6.
FHB4
FEB4
4
4
FHB3
FEB3
3
3
FHB2
FEB2
2
2
FHB1
FEB1
1
1
FHB0
FEB0
“Device Signa-
0
0
2586K–AVR–01/08