Adc Sampling; Wdt Overflow Reset; Prm Register; E-Ice Hirc Trim Operating Description - Holtek HT66F30 User Manual

ADC Sampling

In order to increase ADC sampling stability, it is recommended to add a 0.1F
non-polarized capacitor between each ADC channel and GND. The capacitor should be
located as closed to the DEV as possible.
If this capacitor is not connected, there may be 0~5 data value errors between the
sampled and the expected value which accounts for about 0~7mV.
Additionally, it is recommended to use an external power supply for VDD instead of using
the internal power. To do this, set jumper J8 to position 2-3 and connect an accurate
external power supply which will help to increase the ADC sample accuracy.

WDT Overflow Reset

If the WDT, in the normal mode, is required to overflow repeatedly, it may stop
overflowing after a period of time and the following condition may occur:

Reset and power on reset may fail.

Unable to STOP
These are ICE restrictions. To rectify, re-plug the USB interface and re-compile the
program to continue operation.

PRM Register

For those MCUs with the PRM registers, the MCUs with the pin switch function can be
applied with more flexibility. If no pin function should be changed, the PRM register
setting can be ignored and it default value is 00H. If the pin function is to be changed,
enable the pin switch function and give values according to actual needs. For details refer
to the datasheet on Holtek's official website.

e-ICE HIRC Trim Operating Description

After Manufacture with no Prior Frequency Calibration then Manual
Adjustment will be Required
In this situation, after connecting to the e-ICE, the final configuration option selection is
"ICE_HIRC_Trim". The IDE3000 provides a trimming interface for users to execute an
HIRC Trim function.
Note：
1. Each time a Project Rebuild is executed, a HIRC Trim should be re-executed.
2. Each time the HIRC frequency is changed, a HIRC Trim should be re-executed.
3. Each time the DEV Board is changed, a HIRC Trim should be re-executed.
4. After the Trim process has completed, if the HIRC frequency and DEV Board are not
changed, then the relevant information regarding the Trim will be stored automatically
without needing to re-trim again.
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e-ICE User's Guide