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Rev. 1.21
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Rev. 1.21
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HT66F488/HT66F489
A/D Flash MCU with EEPROM
HT66F488/HT66F489
A/D Flash MCU with EEPROM
Note: * may be resistor or capacitor. The resistance of * must be greater than 1k or the capacitance
of * must be less than 1nF.
On-Chip Debug Support – OCDS
There is an EV chip, HT66V488/489, which is used to emulate the HT66F488/HT66F489 device.
This EV chip device also provides an “On-Chip Debug” function to debug the device during the
development process. The EV chip and the actual MCU devices are almost functionally compatible
except for the “On-Chip Debug” function. Users can use the EV chip device to emulate the real chip
device behavior by connecting the OCDSDA and OCDSCK pins to the Holtek HT-IDE development
tools. The OCDSDA pin is the OCDS Data/Address input/output pin while the OCDSCK pin is the
OCDS clock input pin. When users use the EV chip for debugging, other functions which are shared
with the OCDSDA and OCDSCK pins in the actual MCU device will have no effect in the EV chip.
For a more detailed OCDS description, refer to the corresponding document named “Holtek e-Link
for 8-bit MCU OCDS User’s Guide”.
Holtek e-Link Pins
EV Chip Pins
Pin Description
OCDSDA
OCDSDA
OCDS Data/Add�ess input/output
OCDSCK
OCDSCK
OCDS Clock input
VDD
VDD
Powe� Supply
G�D
VSS
G�ound