attiny15l ATMEL Corporation, attiny15l Datasheet - Page 55

• Manufacturer Part Number: attiny15l
• Description: Attiny15l 8-bit Microcontroller With 1k Byte Flash
• Manufacturer: ATMEL Corporation

Calibration Byte
Programming the Flash
High-voltage Serial
Programming
1187H–AVR–09/07
The ATtiny15L has a one-byte calibration value for the internal RC Oscillator. This byte
resides in the high byte of address $000 in the signature address space. To make use of
this byte, it should be read from this location and written into the normal Flash Program
memory. At start-up, the user software must read this Flash location and write the value
to the OSCCAL Register.
Atmel’s ATtiny15L offers 1K byte of In-System Reprogrammable Flash Program mem-
ory and 64 bytes of in-System Reprogrammable EEPROM Data memory.
The ATtiny15L is shipped with the On-chip Flash program and EEPROM data memory
arrays in the erased state (i.e., contents = $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 cur-
rent of significance is drawn by this pin (less than 100
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 mode. 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 24.
Table 24. Supply Voltage during 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
ATtiny15L
SERIAL CLOCK INPUT
Low-voltage Serial Programming
11.5 - 12.5V
2.7 - 5.5V
PB5 (RESET)
PB3
GND
ATtiny15/L
VCC
PB2
PB1
PB0
High-voltage Serial Programming
4.5 - 5.5V
µA)
SERIAL DATA OUTPUT
SERIAL INSTR. INPUT
SERIAL DATA INPUT
. The Low-voltage Serial
4.5 - 5.5V
ATtiny15L
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