ATMEGA169 ATMEL [ATMEL Corporation], ATMEGA169 Datasheet - Page 349

• Manufacturer Part Number: ATMEGA169
• Description: 8-bit Microcontroller with 16K Bytes In-System Programmable Flash
• Manufacturer: ATMEL [ATMEL Corporation]

Errata
ATmega169 Rev E
ATmega169 Rev D
2514P–AVR–07/06
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1. Interrupts may be lost when writing the timer registers in the asynchronous
•
• High serial resistance in the glass can result in dim segments on the LCD
•
3. Interrupts may be lost when writing the timer registers in the asynchronous
2. High serial resistance in the glass can result in dim segments on the LCD
1. IDCODE masks data from TDI input
Interrupts may be lost when writing the timer registers in the asynchronous timer
Interrupts may be lost when writing the timer registers in the asynchronous timer
IDCODE masks data from TDI input
timer
If one of the timer registers which is synchronized to the asynchronous timer2 clock
is written in the cycle before a overflow interrupt occurs, the interrupt may be lost.
Problem Fix/Workaround
Always check that the Timer2 Timer/Counter register, TCNT2, does not have the
value 0xFF before writing the Timer2 Control Register, TCCR2, or Output Compare
Register, OCR2.
timer
If one of the timer registers which is synchronized to the asynchronous timer2 clock
is written in the cycle before a overflow interrupt occurs, the interrupt may be lost.
Problem Fix/Workaround
Always check that the Timer2 Timer/Counter register, TCNT2, does not have the
value 0xFF before writing the Timer2 Control Register, TCCR2, or Output Compare
Register, OCR2.
Some display types with high serial resistance (>20 kΩ) inside the glass can result
in dim segments on the LCD
Problem Fix/Workaround
Add a 1 nF (0.47 - 1.5 nF) capacitor between each common pin and ground.
The JTAG instruction IDCODE is not working correctly. Data to succeeding devices
are replaced by all-ones during Update-DR.
Problem Fix / Workaround
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If ATmega169 is the only device in the scan chain, the problem is not visible.
Select the Device ID Register of the ATmega169 by issuing the IDCODE
instruction or by entering the Test-Logic-Reset state of the TAP controller to
read out the contents of its Device ID Register and possibly data from
succeeding devices of the scan chain. Issue the BYPASS instruction to the
ATmega169 while reading the Device ID Registers of preceding devices of
the boundary scan chain.
If the Device IDs of all devices in the boundary scan chain must be captured
simultaneously, the ATmega169 must be the first device in the chain.
ATmega169/V
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