Цитата(Slider_spb @ Apr 3 2008, 18:49)

Но это первый раз: включаем питание, программируем в режиме отладчика, запускаем, однократно прерывание генериться, затем тишина..
А чтение SPSR в обработчике прерывания?
Цитата
SPIF
SPI transfer complete flag. When 1, this bit indicates when a SPI data transfer is
complete. When a master, this bit is set at the end of the last cycle of the transfer.
When a slave, this bit is set on the last data sampling edge of the SCK. This bit is
cleared by first reading this register, then accessing the SPI data register.
Цитата
SPI Interrupt
SPI interrupt flag. Set by the SPI interface to generate an interrupt. Cleared by writing
a 1 to this bit.
Note: this bit will be set once when SPIE=1 and at least one of SPIF and WCOL bits
is 1. However, only when SPI Interrupt bit is set and SPI Interrupt is enabled in the
VIC, SPI based interrupt can be processed by interrupt handling software.
Также Errata почитайте по поводу очистки флага прерывания и работы SPI в slave режиме.