AT90S8515-8AC Atmel, AT90S8515-8AC Datasheet - Page 3

• Manufacturer Part Number: AT90S8515-8AC
• Description: IC MCU 8K FLSH 8MHZ 44TQFP
• Manufacturer: Atmel
• Series: AVR® 90Sr

Specifications of AT90S8515-8AC

• 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
• Oscillator Type: Internal
• Operating Temperature: 0°C ~ 70°C
• Package / Case: 44-TQFP, 44-VQFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Data Converters: -

1. Skip Instruction with Interrupts
2494A–09/01
A skip instruction (SBRS, SBRC, SBIS, SBIC, CPSE) that skips a 2-word instruction needs three clock cycles. If an
interrupt occurs during the first or second clock cycle of this skip instruction, the return address will not be stored cor-
rectly on the stack. In this situation, the address of the second word in the 2-word instruction is stored. This means that
on return from interrupt, the second word of the 2-word command will be decoded and executed as an instruction. The
AT90S8515 has two 2-word instructions: LDS and STS.
Note 1: This can only occur if all of the following conditions are true:
- A skip instruction is followed by a 2-word instruction.
- The skip instruction is actually skipping the 2-word instruction.
- Interrupts are enabled, and at least one interrupt source can generate an interrupt.
- An interrupt arrives in the first or second cycle of the skip instruction.
Note 2: This will cause problems only if the address of the following LDS or STS command points to an address
beyond 400 Hex.
Problem Fix/Workaround
For assembly program, avoid skipping a 2-word instruction if interrupts are enabled.
The following C-compilers handles this sequence correctly:
–
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Codevision Compiler, version 1.0.0.5 or higher
IAR Compiler, version 1.40b or higher
Image Craft compiler, all versions
AT90S8515 Errata
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