I was wondering if anybody has ever built an EEPROM programmer based on the 8052-BASIC.

I have finished building mine, as described in the "Microcontroller Idea Book". The circuit is designed to program EEPROMs or NVRAMs starting at 8000H in extenal code memory. These chips are programmed by using the BASIC xby() command.

The programmer has one bug: I cannot write to the address 8000h. I can write to 7fffh, 8001h and so on. For example, if I type

> XBY(8000h) = 255

the computer is supposed to write FFh to 8000h. The computer seems to execute the command, since I get no error codes. If I check that the operation is executed,

> PRINT XBY(8000h)

the answer comes

>255

However, if I reset the system, and read again the value at 8000h, the previous value appears (as if the last write operation never happended). This problem occurs ONLY at this particular address, as far as I can tell. I can write just fine at 8001h, 8002h, 9000h, 9001h, etc.

Does anybody have any similar experiences with this?