I'm working on a project that started with a smaller device but ran out of I/O so was considering the ATTINY48/88 series. One thing I need to do is communicate with a sensor using I2C. It wasn't going to be a problem with the previous ATTINY device, but with this device it shows the top speed in master mode is 25 kHz when the internal 8 MHz oscillator used as the clock. The formula reduces down to fscl = fclk / 320 when using it as a master with the lowest prescaler of 1. Am I missing something? 25 kHz is only 1/4 the lowest "standard" I2C speed of 100 kHz. I was planning to use a different lower-frequency clock (for power savings and other reasons), and with it I can't even hit the minimum sensor I2C clock frequency.