2.01

HT48R50A-1/HT48C50-1
Revision # 2.01
I/O Type 8-bit MCU
Modifications made on January 9, 2009

The Instruction Set section was modified.

The Instruction Definition section was modified.

The Package Information section was modified.

The Product Tape and Reel Specifications section was modified.
Revision # 2.00

The Pin Description table was modified.
Revision # 1.90

Modifications made on May 30, 2005
Technical Document section was added.
Revision # 1.70

Modifications made on November 4, 2005
The Pad Assignment section was deleted.
Revision # 1.80

Modifications made on March 8, 2006
Modifications made on September 21, 2004
At the D.C. Characteristics table, the IDD3 Parameter, as well as Typ. and Max. Conditions
were modified.
Revision # 1.60

Modifications made on June 9, 2004
At the table below the Application Circuits section, the entries of the column for Crystal or
Resonator were modified. A brief functional description for R1 was added at the bottom
portion of the table.
Revision # 1.50
Modifications made on April 26, 2004

The Product Title was modified from 8-Bit I/O Type MCU to I/O Type 8-Bit MCU.

At the D.C. Characteristics table, the Min. value for the RPH 3V was changed from 40kto
20k and the Max. value from 80k to 100k
Revision # 1.40
Modifications made on February 19, 2004

The Block Diagram was modified.

At LVR section, the VLVR values were changed from 3.3V to 3.0V for VDD and from 2.4V to
2.2V for VOPR.

At the Options table, one of the options for System oscillator was changed from Int.
RC+PC3/PC4 to Int. RC+PG1/PG2

At the Timer/Event Counter section, the labels of the TMR0C and TMR1C tables, and the
Timer/Event Counter 0 and Timer/Event Counter 1 diagrams were modified. The
modifications were as follows: from PSC0~PSC2 to T0PSC0~T0PSC2, from TE, TON, TM0,
TM1 to T0E, T0ON, T0M0, T0M1 respectively, etc.
Revision # 1.31

Modifications made on December 16, 2003
At the Instruction Set Summary and Instruction Definition sections, the missing TABRDL
[m] instructions were added back.
Revision # 1.30
Modifications made on August 25, 2003

The PD flag label was changed to PDF flag.

The Application Circuits were modified.
o
The recommended RESET circuitry was modified.
For reasons of stability and noise immunity, the 2-resistor/2-capacitor or
2-resistor/1-capacitor recommended circuits are an improvement over the
1-resistor/1-capacitor circuit. The choice of which circuit is used depends upon
the user application. For example, for battery powered applications the single
resistor and single capacitor circuit may be adequate whereas for applications
such as home appliances, industrial control applications or for circuits which are
close to electrical noise sources, the 2-resistor/2-capacitor circuit may be the
better choice.
o
The Crystal OSC application circuitry was also modified
The recommended additional resistor has been added to ensure that the oscillator
will cease to function when the supply voltage falls below 2.2V to prevent
microcontroller malfunctions. This is because of instabilities in the oscillator at
supply voltages of less than 2.2V.
o
The Instruction Definition section was modified, with the first two columns
deleted.
Revision # 1.20

Modifications made on May 12, 2003
The TMR0, TMR1H and TMR1L entries on the table for the Reset register status were
modified.
Revision # 1.10
Modifications made on January 17, 2003

The system clock label on the block diagram was modified.

At the Oscillator section and other related sections, the WDT period was changed from
78µ s to 65µ s/5V.

At the Watchdog Timer section and other related section, the nominal time-out period
was changed from 16.6ms/5V to 17ms/5V.
Revision # 1.00

This was posted on January 2, 2003
HT48R50A-1 and HT48C50-1 datasheets were combined. Revision number
restarted from 1.00.