
201
8008H–AVR–04/11
ATtiny48/88
Figure 21-7. Serial Programming and Verify
Notes:
1. If the device is clocked by the internal oscillator, it is no need to connect a clock source to the
CLKI pin.
2. VCC - 0.3V < AVCC < VCC + 0.3V, however, AVCC should always be within 1.8 – 5.5V
When programming the EEPROM, an auto-erase cycle is built into the self-timed programming
operation (in the Serial mode ONLY) and there is no need to first execute the Chip Erase
instruction.
The Chip Erase operation turns the content of every memory location in both the Program and
EEPROM arrays into 0xFF.
Depending on CKSEL fuses, a valid clock must be present. The minimum low and high periods
for the serial clock (SCK) input are defined as follows:
Minimum low period of serial clock:
– When f
ck < 12MHz: > 2 CPU clock cycles
– When f
ck >= 12MHz: 3 CPU clock cycles
Minimum high period of serial clock:
– When f
ck < 12MHz: > 2 CPU clock cycles
– When f
ck >= 12MHz: 3 CPU clock cycles
VCC
GND
CLKI
SCK
MISO
MOSI
RESET
+1.8 - 5.5V
AVCC
+1.8 - 5.5V
(2)