HTB RAM Mapping 32×4 LCD Controller For I/o uc Features. Operating voltage: V~V Built-in kHz RC oscillator External kHz crystal or. Holtek HTB: available from 7 distributors. Explore Holtek on Octopart: the fastest source for datasheets, pricing, specs and availability. HT/HTG RAM Mapping 32´4 LCD Controller for I/O MCU PATENTED PAT No.: TW Features · Operating voltage: V~V · 32´4 LCD driver .

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If an on-chip oscillator kHz or an external kHz frequency is chosen as the source of the system frequency, the frequency source is by default prescaled to 32kHz by a 3-stage prescaler. If successive commands have been issued, the command mode ID except for the first command will be omitted. The frequency is calculated by the following equation. The configuration of the system oscillator is as shown.

The darasheet RAM is used as a default. The LCD screen will appear blank.

Download the Holtek HT1621 LCD Controller Datasheet

If successive commands have been issued, the command mode ID except for the first command, will be omitted. The watch dog timer WDTon the other hand, is composed of an 8-stage time base generator along with a 2-stage count-up dtaasheet, and is designed to break the host controller or other subsystems from abnormal states such as unknown or unwanted jump, execution errors, etc. The CS line is used to initialize the serial interface circuit and to terminate the communication between the host controller and the HT The outputs of the time base generator and of the WDT time-out flag can be connected to the IRQ output by a command option.


Remark that we have. The source of the clock may be from an on-chip RC oscillator kHza crystal oscillator As this information may be updated at regular intervals users are reminded to consult the Holtek website http: A simple tone generator is implemented in the HT But if the external clock source dstasheet chosen as the system clock, using the SYS DIS command can neither turn the oscillator off nor carry out the power down mode.

In order to obtain the correct frequency, two additional eatasheet capacities C1, C2 are needed. Here is the functional block diagram directly extracted from the Holtek datasheet. It is recommended that the host controller should read in the data from the DATA line datazheet the rising edge of the RD line and the falling edge of the next RD line.

The value of the driving clock is always Hz even when it is at a Functional operation of this device at other conditions beyond those listed in the specification is not implied and prolonged exposure to extreme conditions may affect device reliability.

After the system power on, the IRQ will be disabled. If the system clock comes from an external clock source, the external clock source should be connected to the OSCI pad.

The tone generator can output a pair of differential driving signals on the BZ and BZ, which are used to generate a single tone. Taipei Sales Office 4F-2, No. The bold form of 1 0 0, namely 1 0 0, indicates the command mode ID.

Macduino: HT a seven segments LCD driver

Yes Yes Yes Yes X: The configuration of the time base generator along with the WDT are as shown. Adresses are organized as displayed in Figure 2. Datasjeet pins are connected as follows: It is recommended that the host controller read in correct data during the interval between the rising edge and the next falling edge of the RD signal.


That is, after the external clock source is selected, the HT will continue working until system power fails or the external clock source is removed. The HT contains a power down command to reduce power consumption.

The system clock is used in a variety of tasks included LCD driving clock and tone frequency generation. The LCD driving clock is derived from the system clock. Once the system is disabled or the tone output is inhibited, the BZ and the BZ outputs will remain at low level.

Of these, 1 0 0 indicates the command mode ID. If the CS pin is set to 1, the data and command issued between the host controller and the HT are first disabled and then initialized. In the case of on-chip RC oscillator or crystal oscillator, the power down mode can reduce power consumption since the oscillator can be turned on or off by the corresponding system commands. We provide procedures to software simulate the internal HT internal RAM and have transparent reading procedures.

Command The mode command should be issued before the data or command is transferred.