Rainbow Electronics ATtiny43U - Manual (Page 142)

142
8048B–AVR–03/09
ATtiny43U
19.3.1 Signature Bytes
All Atmel microcontrollers have a three-byte signature code which identifies the device. This
code can be read in both serial and High-voltage Programming mode, also when the device is
locked.
Signature bytes can also be read by the device firmware. See section “Reading the Fuse and
Lock Bits from Software” on page 135 .
The three signature bytes reside in a separate address space called the device signature imprint
table. The signature data for ATtiny43U is given in
Table 19-7 .
19.3.2 Calibration Byte
The device signature imprint table of ATtiny43U contains one byte of calibration data for the
internal oscillator, as shown in
Table 19-6 on page 141 . During reset, this byte is automatically
written into the OSCCAL register to ensure correct frequency of the calibrated oscillator.
Calibration bytes can also be read by the device firmware. See section “Reading the Fuse and
Lock Bits from Software” on page 135 .
19.4 Page Size
19.5 Parallel Programming Parameters, Pin Mapping, and Commands
This section describes how to parallel program and verify Flash Program memory, EEPROM
Data memory, Memory Lock bits, and Fuse bits in the ATtiny43U. Pulses are assumed to be at
least 250 ns unless otherwise noted.
19.5.1 Signal Names
In this section, some pins of the ATtiny43U are referenced by signal names describing their
functionality during parallel programming, see
Figure 19-1 and Table 19-10 . Pins not described
in the following table are referenced by pin names.
Table 19-7. Device Signature Byte
Part Signature Byte 0 Signature Byte 1 Signature Byte 0
ATtiny43U 0x1E 0x92 0x0C
Table 19-8. No. of Words in a Page and No. of Pages in the Flash
Device Flash Size Page Size PCWORD No. of Pages PCPAGE PCMSB
ATtiny43U
2K words
(4K bytes)
32 words PC[4:0] 64 PC[10:5] 10
Table 19-9. No. of Words in a Page and No. of Pages in the EEPROM
Device EEPROM Size Page Size PCWORD No. of Pages PCPAGE EEAMSB
ATtiny43U 64 bytes 4 bytes EEA[1:0] 16 EEA[5:2] 5