HDH datasheet, HDH pdf, HDH data sheet, datasheet, data sheet, pdf, Hitachi Semiconductor, LCD Driver with Channel Outputs. HDH from Hitachi, Ltd.. Find the PDF Datasheet, Specifications and Distributor Information. HDH Datasheet PDF Download – LCD Driver with Channel Outputs, HDH data sheet.

Author: Nijin Mazutaxe
Country: Tanzania
Language: English (Spanish)
Genre: Software
Published (Last): 5 November 2004
Pages: 346
PDF File Size: 3.53 Mb
ePub File Size: 5.86 Mb
ISBN: 201-7-95284-743-6
Downloads: 51978
Price: Free* [*Free Regsitration Required]
Uploader: Vudojas

Character LCD module is one of the display device that well used for electornics equipments. Its ability to dislpaly alpha-numeric characters has contributed the improvement of function of the electronics devices. Especially its very low power consumption is suitable for battery powered devices.

HDH Datasheet PDF –

Of course it is also used for electronics handiworks as like 7-segment LED display. The HD or compatibles is embedded in most of character LCD modules manufactured now; therefore learning the function of HD is a necessary and sufficient condition to use character LCD modules. Following shows the features of HD Therefore for that days it was a wonderful chip set that can build character LCD module with only a controller IC.

It has occupied the market of character LCD controller and established the position of de facto standard. The HD has being used for a quarter of a century without changes from the original design.

This is a rare case as an application specific digital IC. It can also be modified as mask option.


The maximum panel size that can control with an HD itself is 8 columns by 2 rows. To control larger LCD panels upto 40 columns, one or more segment expansion driver chip, Ratasheet or compatibles, is required as shown in Figure 2a.

Also it can support various panel organezations described below. Normally this is configured by 1-row driving mode using only half of COM lines and a segment expansion driver. To eliminate the segment expansion driver, it can also be configured based on 8 by 2 mode by placing the second row to right side of the first row as shown in Figure 2b. Therefor 1-row driving mode is not used except for 8 by 1 panel. This is the maximum configuration that using two HDs.

The bottom line of dh44100h row is used for under-line cursor. In some modules, this line is separated from the character body on the LCD panel that shown in Figure 2d so that the user characters using the bottom line may not be expected appearance.

In this mode, the characters are 10 lines in height and can represent the discener like g, j, p, q and y. However two-row mode cannot be used in this configuration so that the line mode is not used in datasheef CLCD modules. There are three registers, instruction register, status register and data register that visible via host interface. Write only eatasheet register. When an instruction byte is written to this register, the instruction decoder executes the instruction. While the execution is in progress, busy flag BF is set.


The processing time differs with instructions. Read only 8-bit register. The BF is a flag indicates that internal process is in progress and instruction datashewt and data register are not accessible. Before accessing these registers, make sure that BF is cleared. When access the registers without this check, interval of each access must be much longer than execution time. The read operation is also occured on Address Set incstruction.

The BF is set during these operations. The internal registers are not accessible via host interface. They are datashee indirectly by instructions or via data register. Display data buffer that holds character code.

The address range is 00h to 7Fh but only 80 bytes are implemented as shown in Figure 3a. The characters located in 00h to 27h is displayed in the first row and others are displayed in the second row. Character pattern buffer as a part of the character generator. Figure 3a The address range is 00h to 3Fh. In 8-line mode, each 8 locations corresponds to a user character so that 8 user character patterns can be registered in it. The value is hd4100h to next direction is defined by instruction on access to the data register.

It can also be changed to next or loaded a new value. The cursor is displayed at the character being addressed by the address counter. Undocumented register that holds the address of first character displayed at left end of the first row.

The range of the value is 00h to 27h. The address of first character of the second row is 40h added catasheet the value. The characters that pushed out appears at opposit end of the row. The value is changed to next on data register acces if shift operation is enabled by instruction.

It can also be changed to next or cleared by instruction but cannot load datasheeg new value. The data written into the instruction register is decoded and executed by instruction decoder. List 1 shows the each instruction.

There are two configurations on bus width, 8-bit mode and 4-bit mode. The first cycle transfers upper 4 bits and the following cycle transfers lower 4 bits. This sequence must be atomic.

The host interface becomes unknown state in case of the bus sequence is interrupted by system reset or any other reason. The HD does not have an external reset signal.

It has an integrated power-on reset circuit and can be initialized to the 8-bit mode by proper power-on condition. However the reset circuit can not work properly if the supply voltage he44100h too slowly or fast. Therefore the state of the host interface can be an unknown state, 8-bit mode, 4-bit mode or half of 4-bit cycle at datssheet started.

To initialize the HD correctly even if it is unknown state, the software reset procedure shown in Figure 4 is recommended prior to initialize ud44100h HD to the desired function.

Figure 5a shows the typical circuit diagram to use the CLCD module. The interface pin connections on the module is shown in Figure 5b in pin layout of single-inline or dual-inline.


Some modules have additional two pins for the back-light. Note that Vcc and GND are reversed on some modules. The host interface type of HD is for series becuse Hitachi had supplied Motorola series as a second source.

However it hhd44100h intended to use at 1 to 2 MHz bus frequency so that it ddatasheet difficult to connect to modern high speed bus and also most microcontroller does he44100h have extrenal bus. Figure 5b shows the typical timing diagram of the host interface. The bus timing is not that fast enough compared to datawheet speed of GPIO port.

Consderation of bus timing, especially pulse width of E signal, is needed. The bus timing varies by supply voltage and also there are some difference of timings among the compatible chips. When control the module as fast as maximum speed, make sure the detailed timing of the controller chip on the CLCD module to be used. Lower 4 bits of the hd444100h bus, DB3 to DB0, are not used in 4-bit mode.

The datasheet says that these pins should be left opened in 4-bit configuration as shown in Figure 6a. However they are tied to GND in a number of cases as shown in Figure 6b. There are two methods, Polling and Delay, to wait for the end of internal process of the HD The first one continues to read status register until BF goes zero and the other skips the internal processing time by a simple delay.

Both these methods are defined by datasheet. Because there is the BF for this purpose, the polling method is considered primary.

However actually the delay method is used in most products. Contrary to general belief, the advantage he44100h the polling method is only display speed but it is not even an advantage. Because the response time of LCD panel is about miliseconds, such the fast update is an useless feature. Thus the delay method is much superior in most feature to the polling method. If not, hd444100h metal frame is tied to GND. When mount the module on the metal case, the metal frame should be disconnected from GND in order to avoid a short circuit of SG and FG.

When mount it on the plastic case or without the case, the metal frame should be grounded to avoid electric damages due to ESD. Block Diagram Figure 1. Programming Model Host Interface There are three registers, instruction register, status register and data register that visible via host interface. Instruction Register Write only 8-bit register. Status Register Read only 8-bit register. Intrenal Dataasheet Figure 3. Software Reset and Initialization.