AT89Sxx Cheap and Simple Learning Board
Tahan Prahara, prahara_satria@yahoo.co.id
Build your own a cheap simple Microcontroller learning board S-52. The board is based on ATMEL's new ISP chip AT89S51, AT89S52, or AT89S53. This board can be used by beginners for learning Assembly and C language programming. Single sided PCB file included.
Introduction
I have designed this leaning board to
be used as a tool for learning MCS-51 Microcontrollers.
The AT89Sxx learning board features,
Hardware
The board design is kept as simple as possible so that everone can make the learning board easily. The schematic shown below shows the complete hardware schematic of the AT89Sxx learning board. PORT0, PORT1, PORT2, and PORT3 are available for interfacing external devices. P3.0 and P3.1 are being used for RS232 interface.

Figure1: Complete hardware schematics: MCU, and power supply
Bill of Materials
R1 330 1/4W +/-5%
R2 10K 1/4W +/-5%
R3-10 10K 1/4W +/-5% (for pull up on P0)
C1 1000uF/16V electrolytic capacitor
C2 100uF/16V electrolytic capacitor
C3 100nF multilayer or ceramic
C4 10uF/16V electrolytic
C5,C6 33pF ceramic
D1 1N4001 / 1N4002 silicon rectifier diode
D2 LED
U1 LM7805, voltage regulator
U1 AT89S51, AT89S52 or AT89S53
X1
DB25 parallel port, 25pins connector
Construction
In order to make the AT89Sxx learning board, download the PCB ZIP file click on PCB ZIP FILES link given below. The file contains the single sided PCB track layout in PDF. Use the convenient file for making the PCB. Put the components as shown in the picture shown below.
How to make PCB?

Figure2: Component placement layout.


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Figure3. AT89Sxx Cheap and Simple Learning Board
Code Programming
The SPI In system Programming adapter such as Cheap Loader Cable of Asim's ISP for 89S51 89S52 can be used for program loading to the MCU. Connect the ISP adapters 6 pin connector with the 6 pin ISP header on this board. Run the ISP software on PC for sending the Intel hex file to microcontroller. Then program will start running.

Figure4: ISP cable schematics

Figure5: How to connect isp cable to board

Figure6: ISP Flash Programmer

Any questions or suggestions, please contact me,
Tahan Prahara, prahara_satria@yahoo.co.id