ATtiny15L
49
Programming the Flash
Atmel’s ATtiny15L offers 1K bytes of in-system reprogrammable Flash Program memory and 64 bytes of in-system repro-
grammable EEPROM data memory.
The ATtiny15L is shipped with the on-chip Flash Program and EEPROM Data memory arrays in the erased state (i.e. con-
tents = $FF) and ready to be programmed.
This device supports a High-voltage (12V) Serial programming mode and a Low-voltage Serial programming mode. The
+12V is used for programming enable only, and no current of significance is drawn by this pin (less than 100
µA). The Low-
voltage Serial programming mode provides a convenient way to download Program and Data into the ATtiny15L inside the
user’s system.
The Program and Data memory arrays in the ATtiny15L are programmed byte-by-byte in either programming modes. For
the EEPROM, an auto-erase cycle is provided within the self-timed write instruction in the Low-voltage Serial programming
mode.
During programming, the supply voltage must be in accordance with Table 23.
Table 23. Supply voltage during programming
High-voltage Serial Programming
This section describes how to program and verify Flash Program memory, EEPROM Data memory, Lock bits and Fuse bits
in the ATtiny15L.
Figure 30. High-voltage Serial Programming
Part Low-voltage Serial programming High-voltage Serial programming
ATtiny15L 2.7 - 5.5V 4.5 - 5.5V
PB5 (RESET)
PB3
GND
VCC
PB2
PB1
PB0
SERIAL DATA OUTPUT
SERIAL INSTR. INPUT
SERIAL DATA INPUT
SERIAL CLOCK INPUT
11.5 - 12.5V 4.5 - 5.5V
ATtiny15/L