Controlling the Address bus and Data bus

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One of the main features of the Tester is that it can take control of the Address and Data buses of the UUT by removing the UUT microprocessor and plugging in a suitable POD where the processor normally resides.

Once plugged in and the UUT is powered up, full control of the buses can be achieved.

The LED display will show the current NEXT Address value and the Data in HEX. As it is a 8 bit emulator, the address bus is 16bits allowing values from 0000h to FFFFh and the data is 8 bits so values 00h to FFh are possible,

To set the address to a defined value, click the Address box on the MAIN TEST SCREEN and type in the value required. Numbers 0-9 and letters A-F are acceptable and should be in CAPTIALS or Lower Case.

Once an Address is entered, Click the ADDR WRITE button and the LED display will indicate the address selected. At this point the Address bus of the UUT will also be set to this value so for example if 0001h is set, all the Address bus pins will be set to 0 except A0 will be 1.

The Data bus is controlled the same way except data can be bi directional so data can be read back from the UUT. Click either DATA WRITE or DATA READ depending on what function is required.

Once set, the pins remain set until further functions are performed or the tester changes the address.