Epson S1D13705 Hardware Abstraction Layer HAL, Introduction, Contents of the Halstruct

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	Vancouver Design Center

9 Hardware Abstraction Layer (HAL)

9.1 Introduction

The HAL is a processor independent programming library provided by Epson. The HAL was developed to aid the implementation of internal test programs, and provides an easy, consistent method of programming the S1D13705 on different processor platforms. The HAL also allows for easier porting of programs between S1D1370X products. Integral to the HAL is an information structure (HAL_STRUCT) that contains configuration data on clocks, display modes, and default register values. This structure combined with the utility 13705CFG.EXE allows quick customization of a program for a new target display or environment.

Using the HAL keeps sample code simpler, although some programmers may find the HAL functions to be limited in their scope, and may wish to program the S1D13705 without using the HAL.

9.2 Contents of the HAL_STRUCT

	The HAL_STRUCT below is contained in the file “hal.h” and is required to use the HAL library.
typedef struct tagHalStruct
{
char	szIdString[16];
WORD	wDetectEndian;
WORD	wSize;
BYTE	Regs [MAX_REG + 1];
DWORD	dwClkI;	/* Input Clock Frequency (in kHz) */
DWORD	dwDispMem;	/* Starting address of display buffer memory */
WORD	wFrameRate;	/* Desired panel frame rate */

} HAL_STRUCT;

Within the Regs array ia a structure which defines all the registers described in the S1D13705 Hardware Functional Specification, document number X27A-A-001-xx. Using the 13705CFG.EXE utility you can adjust the content of the registers contained in HAL_STRUCT to allow for different LCD panel timing values and other default settings used by the HAL. In the simplest case, the program only calls a few basic HAL functions and the contents of the HAL_STRUCT are used to setup the S1D13705 for operation.

S1D13705	Programming Notes and Examples
X27A-G-002-03	Issue Date: 02/01/22