Datasheet

19
AVR061
2525B–AVR–04/03
Oscillator Timer
Prescaler Value
Sets or retrieves the current prescaler value for the timer in the mcu that is used to gen-
erate the adjustable Oscillator. The actual Oscillator frequency is a function of the
Parm_STK_OSC_PSCALE and the Parm_STK_OSC_CMATCH parameters. See the
Table 35 below.
Parameter Parm_STK_OSC_PSCALE
Access: Read/Write
Parameter Value 0x86
Oscillator Timer
Compare Match Value
Sets or retrieves the current compare match value for the timer in the mcu that is used to
generate the adjustable Oscillator. See the description of the
Parm_STK_OSC_PSCALE parameter.
Parameter Parm_STK_OSC_CMATCH
Access: Read/Write
Parameter Value 0x87
ISP SCK Duration Sets or retrieves the parameter for the current ISP SCK half-period duration. To ensure
correct programming, this parameter should be set to the following criteria:
[Parm_STK_SCK_DURATION] > (8*10^6 / target_freq) - 2
Parameter Parm_STK_SCK_DURATION
Access: Read/Write
Parameter Value 0x89
Table 35.
Value Oscillator Frequency
0 Oscillator off
1 mcu_freq/(([Parm_STK_OSC_CMATCH] + 1) * 1 * 2)
2 mcu_freq/(([Parm_STK_OSC_CMATCH] + 1) * 8 * 2)
3 mcu_freq/(([Parm_STK_OSC_CMATCH] + 1) * 32 * 2)
4 mcu_freq/(([Parm_STK_OSC_CMATCH] + 1) * 64 * 2)
5 mcu_freq/(([Parm_STK_OSC_CMATCH] + 1) * 128 * 2)
6 mcu_freq/(([Parm_STK_OSC_CMATCH] + 1) * 256 * 2)
7 mcu_freq/(([Parm_STK_OSC_CMATCH] + 1) * 1024 * 2)
Table 36.
Value Description
– –
Table 37.
Value Description
– –