What it is

This C-library contains hardware abstraction layer (HAL) for STC15W408AS.

STC15W408AS is a micro chip compatible with 8051 architecture.

How to use it

This code is published as Platformio library named STC15 hardware.

Add library to your project

After create Platformio project for STC15408AS add to platformio.ini line with library depandency

[env:STC15W408AS]
platform = intel_mcs51
board = STC15W408AS
lib_deps = mgoblin/STC15 hardware@^0.8.0

Where is 0.7.0 STC15 hardware library version.

As alternative in lib_deps line github link could be used.

[env:STC15W408AS]
platform = intel_mcs51
board = STC15W408AS
lib_deps = https://github.com/mgoblin/STC15lib#0.8.0

Where is 0.8.0 STC15 hardware library github tag version.

Each released library version has the tag in github repository.

Low level STC15 prorgamming

You can directly manipulate to MCU registers from C-code. STC15Fxx.h should be included.

#include <STC15Fxx.h> // MCU SFR declarations 

void main()
{
    // Use SFR declaration to change MCU state here

    P10 = 0; // As example put LED on. Pin P1.0 connected to onboard LED
}

Use STC15 HAL functions

This library provides hardware astraction laywer (HAL) for high level development tasks. Please read the docs for library modules in Library documentation section (see the docs link).

Most of HAL functionality is C-macros.

The advantage is small firmware code size because macroses are expanded into application.

C-Macroses have some drawbacks.

1. No compiler typechecks
2. No function call optimizations. Macroses code inlined.

If you need to use one HAL macros many times the good idea is to wrap macros by C-function.

#include <delay.h>

#define LED P10
#define ON 0
#define OFF 1

// Wrap delay_ms HAL macros call to C-function
void f_delay_ms(uint16_t ms)
{
    delay_ms(ms); // This is a macros 
} 

void main()
{
    while(1)
    {
        LED = ON;
        f_delay_ms(500);
        LED = OFF;
        f_delay_ms(1000);
    }
}

Library modules maturity

Module name	Description	Maturity
ChipID	Get chip id from ROM	READY
Delay	CPU cycles based delay	READY
CPU frequency	CPU frequency slowdown	READY
Interrupt	Enable and disable interrupts	READY
Power management	idle, powerdown and wakeup timer	READY
Reset	Software reset	READY
Timer	Timer control routines	READY
UART	Serial port routines	INITIAL SUPPORT
Watchdog timer	Watchdog timer routines	READY
Pin	Pin as digital in/out routines	READY

Other modules does not implemented yet.

See examples in https://github.com/mgoblin/STC15lib/tree/main/examples

Library documentation

Docs

Version history

Version history

References

• STC datasheets: http://stcmicro.com/sjsc.html
• SDCC User Guide (PDF): http://sdcc.sourceforge.net/doc/sdccman.pdf
• STC programmator https://github.com/mgoblin/STC-programmatorhttps://github.com/mgoblin/STC-programmator