MC81F4204April 24, 2012 Ver.1.41 13725. IN SYSTEM PROGRAMMING25.1 Getting StartedThe In-System Programming (ISP) is an ability to program the code into the MCU while it is installedin a complete system.USB_SIO_ISP uses both USB to communicate with PC and SIO to communicate with MCU. That iswhy we call it as ‘USB_SIO_ISP’. In fact there are another ISP types. So remember that allMC81F4xxx series use ‘USB_SIO_ISP’.Here is a procedure to use ISP.1. Power off the target system.If you use the RESET/Vpp pin as an output mode, power on timing is very important.So you must read ‘Entering ISP mode at power on time’ and strictly obey the procedure.2. Install the USB_SIO_ISP software. (It is required at only first time)1) Download the ISP software from http://www.abov.co.kr2) Unzip the downloaded file and connect the USB_SIO_ISP board.3) Install the driver for USB_SIO_ISP. (There is a driver file in the zip file.)3. Make sure the hardware condition is satisfied. And connect the ISP cable.See ‘25.3 Hardware Conditions to Enter the ISP Mode’ page 140,4. Run the software and select a device.All commands are enabled after select the device.5. Power on the target system.If you use the RESET/Vpp pin as an input mode, power on timing is not that important.But make sure the power is turned-on before execute the ISP commands.6. Execute ISP commands as you want.If you want to write a code into your MCU, it is recommendable to do following step.‘Load File’ -> ‘Auto’( while ‘Auto Option Write’ and ‘Auto Show Option’ options areenabled ).After finish an ISP command is executed, the MCU enters to normal operation mode automatically. Soyou can see the system is working right after the ISP command is finished. ( ‘Auto’ is assumed as onecommand’)In fact, it is possible to repeat the step-6 until the hardware condition is changed. But in case ofRESET/Vpp pin is used as an output mode, do not repeat step-6. In that case, you must follow theprocedure. See ‘Entering ISP mode at power on time’ for more information.After you change the ‘Rom Option’, you must do power-off and power-on to reflect the changed ‘RomOption’, even you can repeat the step-6 and see the changed code’s operation without doing it. TheMCU reads the ‘Rom option’ when only the ‘power on reset time’.