AT90S8535-8AI Atmel, AT90S8535-8AI Datasheet - Page 2

• Manufacturer Part Number: AT90S8535-8AI
• Description: IC MCU 8K 8MHZ A/D IT 44TQFP
• Manufacturer: Atmel
• Series: AVR® 90Sr

Specifications of AT90S8535-8AI

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 8MHz
• Connectivity: SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 32
• 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): 4 V ~ 6 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 44-TQFP, 44-VQFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

6. Error in Writing Reset Status Bits
5. Wake-up from Sleep Executes Instructions before the Interrupt is Serviced
4. The SPI Can Send Wrong Byte
3. Serial Programming at Voltages below 3.0V
2. Wake-up from Power-save without Global Interrupt Enabled
1. UART Loses Synchronization if RXD Line is Low when UART Receive is Disabled
Significant Datasheet Changes
2
The EXTRF flag in MCUSR will be cleared when clearing the PORF-flag. The flag does not get cleared by writing a “0”
to it.
Problem Fix/Workaround
Finish the test of both flags before clearing any of them. Clear both flags simultaneously by writing “0” to both PORF
and EXTRF in MCUCR.
When waking up from Power-save, some instructions are executed before the interrupt is called. If the device is woken
up by an external interrupt, 2 instruction cycles are executed. If it is woken up by the asynchronous timer, 3 instructions
are executed before the interrupt.
Problem Fix/Workaround
Make sure that the first two or three instructions following sleep are not dependent on the executed interrupt.
If the SPI is in Master mode, it will restart the old transfer if new data is written on the same clock edge as the previous
transfer is finished.
Problem Fix/Workaround
When writing to the SPI, first wait until it is ready, then write the byte to transmit.
At voltages below 3.0V, serial programming might fail.
Problem Fix/Workaround
Keep V
When an asynchronous timer interrupt is used to wake up the part from Power-save, the part will wake up even if global
interrupts are disabled.
Problem Fix/Workaround
No workaround necessary.
The UART will detect a UART start bit and start reception even if the UART is not enabled. If this occurs, the first byte
after re-enabling the UART will be corrupted.
Problem Fix/Workaround
Make sure that the RX line is high at start-up and when the UART is disabled. An external RS-232 level converter
keeps the line high during start-up.
Revision D and older contained an errata allowing PORTD register to change the state of the output compare value of
Timer/Counter1. This error is described as errata #7 in AT90S/LS8535 revision D erratasheet. Because of the high like-
lihood of users to experience this error, the erratic behaviour was also described in the databook.
From revision E this errata is corrected. Writing to PORTD5 and PORTD4 will not set the OC1A and OC1B respectively
and the datasheet has been changed to describe the correct device behaviour (datasheet revision 1041H or later).
AT90S/LS8535 Errata
CC
at 3.0V or higher during In-System Programming.
1657C–11/01