Holtek HT66F30 User Manual page 14


Click the "ICE_HIRC Trim" from the Option menu, then scroll and use an oscilloscope
to check that Fsys is the desired HIRC frequency.
 The Flat Tuning is the HIRC coarse adjustment while the Fine tuning is the HIRC
fine adjustment as shown as figure 17.
 As scrolling approaches the Max value the frequency will increase
 The present HIRC frequency can be measured on the Fsys pin on the DEV (A13 of
J1) as shown in figure 18.
 The oscilloscope detection method is shown in figure 19.
Figure 17 HIRC Trimming Interface
Figure 18 f
Every time the Trim value is adjusted
the IDE3000 will download the
temporary operating file to the e-ICE
Measuring Point
SYS
14
e-ICE User's Guide
Coarse adjustment
Fine adjustment
A13: f
SYS