ATXMEGA256A3B-MH Atmel, ATXMEGA256A3B-MH Datasheet - Page 99
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ATXMEGA256A3B-MH
Manufacturer Part Number
ATXMEGA256A3B-MH
Description
MCU AVR 256KB FLASH A3B 64-QFN
Manufacturer
Atmel
Series
AVR® XMEGAr
Specifications of ATXMEGA256A3B-MH
Core Processor
AVR
Core Size
8/16-Bit
Speed
32MHz
Connectivity
I²C, SPI, UART/USART
Peripherals
Brown-out Detect/Reset, DMA, POR, PWM, WDT
Number Of I /o
49
Program Memory Size
256KB (128K x 16)
Program Memory Type
FLASH
Eeprom Size
4K x 8
Ram Size
16K x 8
Voltage - Supply (vcc/vdd)
1.6 V ~ 3.6 V
Data Converters
A/D 16x12b; D/A 2x12b
Oscillator Type
Internal
Operating Temperature
-40°C ~ 85°C
Package / Case
64-MLF®, 64-QFN
Processor Series
ATXMEGA256x
Core
AVR8
Data Bus Width
8 bit, 16 bit
Data Ram Size
16 KB
Interface Type
I2C, SPI, USART
Maximum Clock Frequency
32 MHz
Number Of Programmable I/os
49
Number Of Timers
7
Operating Supply Voltage
1.6 V to 3.6 V
Maximum Operating Temperature
+ 85 C
Mounting Style
SMD/SMT
3rd Party Development Tools
EWAVR, EWAVR-BL
Development Tools By Supplier
ATAVRDRAGON, ATAVRISP2, ATAVRONEKIT
Minimum Operating Temperature
- 40 C
On-chip Adc
12 bit, 8 Channel
On-chip Dac
12 bit, 2 Channel
For Use With
ATAVRONEKIT - KIT AVR/AVR32 DEBUGGER/PROGRMMRATSTK600 - DEV KIT FOR AVR/AVR32770-1007 - ISP 4PORT ATMEL AVR MCU SPI/JTAG770-1004 - ISP 4PORT FOR ATMEL AVR MCU SPI
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
Other names
ATXMEGA256A3B-MU
ATXMEGA256A3B-MU
ATXMEGA256A3B-MU
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Part Number:
ATXMEGA256A3B-MH
Manufacturer:
ATMEL/爱特梅尔
Quantity:
20 000
8116I–AVR–09/10
18. Crystal start-up time required after power-save even if crystal is source for RTC
19. TWI Transmit collision flag not cleared on repeated start
20. Clearing TWI Stop Interrupt Flag may lock the bus
Problem fix/Workaround
This device revision has only one NMI interrupt source, so checking the interrupt source in
software is not required.
Even if 32.768 kHz crystal is used for RTC during sleep, the clock from the crystal will not be
ready for the system before the specified start-up time. See "XOSCSEL[3:0]: Crystal Oscilla-
tor Selection" in XMEGA A Manual. If BOD is used in active mode, the BOD will be on during
this period (0.5s).
Problem fix/Workaround
If faster start-up is required, go to sleep with internal oscillator as system clock.
The TWI transmit collision flag should be automatically cleared on start and repeated start,
but is only cleared on start.
Problem fix/Workaround
Clear the flag in software after address interrupt.
If software clears the STOP Interrupt Flag (APIF) on the same Peripheral Clock cycle as the
hardware sets this flag due to a new address received, CLKHOLD is not cleared and the
SCL line is not released. This will lock the bus.
Problem fix/Workaround
Check if the bus state is IDLE. If this is the case, it is safe to clear APIF. If the bus state is
not IDLE, wait for the SCL pin to be low before clearing APIF.
Code:
/* Only clear the interrupt flag if within a "safe zone". */
while ( /* Bus not IDLE: */
{
}
/* Check for an pending address match interrupt */
if ( !(COMMS_TWI.SLAVE.STATUS & TWI_SLAVE_CLKHOLD_bm) )
{
}
/* Ensure that the SCL line is low */
if ( !(COMMS_PORT.IN & PIN1_bm) )
/* Safely clear interrupt flag */
COMMS_TWI.SLAVE.STATUS |= (uint8_t)TWI_SLAVE_APIF_bm;
)
((COMMS_TWI.MASTER.STATUS & TWI_MASTER_BUSSTATE_gm) !=
if ( !(COMMS_PORT.IN & PIN1_bm) )
TWI_MASTER_BUSSTATE_IDLE_gc)) &&
/* SCL not held by slave: */
!(COMMS_TWI.SLAVE.STATUS & TWI_SLAVE_CLKHOLD_bm)
break;
XMEGA A3B
99