Thursday, March 11, 2010

ISP cable for AT89Sxx and AVR seires

ISP for 89S51 89S52
SCHEMATIC.PDF modified schematic with onboard USB cable port
LAYOUT.PDF image of PCB layout viewed from the top layer
LAYOUT2.PDF mirror layout
BOM.PDF component lists Asim's Loader Software

Source full copyrights belongs to :

Wichit Sirichote,
Complete page Website 
About ISP complete details : Click here


  1. Hello Sir,

    Firstly thanks for the detailed schematic and layouts. I am trying to build this at home, and I intend to program AT89S52 thorough my laptop. Your clarifications on the following doubts shall be very helpful:

    1) Can the CON10AP (J1), be replaced with a 9pin DB connector? Does the pin connections change if I try to do that? The schematic shows that MISO connects at pin 10, where will it go on the DB9? Using this DB9 can i directly connect to the programmer using a serial to USB connector?

    2)The circuit works on 5V. What is the Voltage regulator that can be used with a 12V supply? Can you please guide me to its schematic as well?

    3) I dis not understand how the USB connector is connecting to the microcontroller? Can you please help me with this?

    Thanks in advance. Appreciate your work.

    1. even i wanted a little insight on working with rs232 and 89s52 and programming through using the laptop.the device is not detected in the isp.

  2. i want to get in touch with u engineer jagan ,,can u please add me up on whatsapp orr call with +2348066115243