ATTINY84-20MU Atmel, ATTINY84-20MU Datasheet - Page 57

• Manufacturer Part Number: ATTINY84-20MU
• Description: IC MCU AVR 8K FLASH 20MHZ 20-QFN
• Manufacturer: Atmel
• Series: AVR® ATtinyr

Specifications of ATTINY84-20MU

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 20MHz
• Connectivity: USI
• Peripherals: Brown-out Detect/Reset, POR, PWM, Temp Sensor, WDT
• Number Of I /o: 12
• Program Memory Size: 8KB (4K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 512 x 8
• Ram Size: 512 x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 20-MLF®, QFN
• Cpu Family: ATtiny
• Device Core: AVR
• Device Core Size: 8b
• Frequency (max): 20MHz
• Interface Type: SPI/USI
• Total Internal Ram Size: 512Byte
• # I/os (max): 12
• Number Of Timers - General Purpose: 2
• Operating Supply Voltage (typ): 3.3/5V
• Operating Supply Voltage (max): 5.5V
• Operating Supply Voltage (min): 2.7V
• On-chip Adc: 8-chx10-bit
• Instruction Set Architecture: RISC
• Operating Temp Range: -40C to 85C
• Operating Temperature Classification: Industrial
• Mounting: Surface Mount
• Pin Count: 20
• Package Type: MLF
• Processor Series: ATTINY8x
• Core: AVR8
• Data Bus Width: 8 bit
• Data Ram Size: 512 B
• Maximum Clock Frequency: 20 MHz
• Number Of Programmable I/os: 12
• Number Of Timers: 2
• Operating Supply Voltage: 2.7 V to 5.5 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: EWAVR, EWAVR-BL
• Development Tools By Supplier: ATAVRDRAGON, ATSTK500, ATSTK600, ATAVRISP2, ATAVRONEKIT
• Minimum Operating Temperature: - 40 C
• Package: 20MLF
• Family Name: ATtiny
• Maximum Speed: 20 MHz
• For Use With: ATSTK600 - DEV KIT FOR AVR/AVR32770-1007 - ISP 4PORT ATMEL AVR MCU SPI/JTAGATAVRISP2 - PROGRAMMER AVR IN SYSTEM
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

8006K–AVR–10/10
Consider the clock period starting shortly after the first falling edge of the system clock. The latch
is closed when the clock is low, and goes transparent when the clock is high, as indicated by the
shaded region of the “SYNC LATCH” signal. The signal value is latched when the system clock
goes low. It is clocked into the PINxn Register at the succeeding positive clock edge. As indi-
cated by the two arrows tpd,max and tpd,min, a single signal transition on the pin will be delayed
between ½ and 1½ system clock period depending upon the time of assertion.
When reading back a software assigned pin value, a nop instruction must be inserted as indi-
cated in
positive edge of the clock. In this case, the delay tpd through the synchronizer is one system
clock period.
Figure 10-4. Synchronization when Reading a Software Assigned Pin Value
The following code example shows how to set port A pins 0 and 1 high, 2 and 3 low, and define
the port pins from 4 to 5 as input with a pull-up assigned to port pin 4. The resulting pin values
are read back again, but as previously discussed, a nop instruction is included to be able to read
back the value recently assigned to some of the pins.
Note:
Assembly Code Example
...
; Define pull-ups and set outputs high
; Define directions for port pins
ldi
ldi
out
out
; Insert nop for synchronization
nop
; Read port pins
in
...
Two temporary registers are used to minimize the time from pull-ups are set on pins 0, 1 and 4,
until the direction bits are correctly set, defining bit 2 and 3 as low and redefining bits 0 and 1 as
strong high drivers.
Figure 10-4 on page
INSTRUCTIONS
r16,(1<<PA4)|(1<<PA1)|(1<<PA0)
r17,(1<<DDA3)|(1<<DDA2)|(1<<DDA1)|(1<<DDA0)
PORTA,r16
DDRA,r17
r16,PINA
SYSTEM CLK
SYNC LATCH
PINxn
r16
r17
57. The out instruction sets the “SYNC LATCH” signal at the
out PORTx, r16
0x00
nop
t
pd
0xFF
in r17, PINx
ATtiny24/44/84
0xFF
57