picaxe 18x 7 segment display
It can be done in one-hundred-and-one ways ..
For example, if you use el-cheapo microcontroller (PICAXE, PIC, or whichever you like), you can define 7 pins as inputs and 4 pins as outputs ..
Or, if you use an EPROM, it can be burned in such a way that 7-segment code is delivered to the address inputs and the 4-lower order outputs carry the translated BCD number. All what you need to program is 10 memory locations ..
So, if address inputs A0-t0-A5 "see" 1s and A6 sees "0" - that's equivalent to 7-segment "0" (a, b, c, d, e, f =ON, g=Off) - the relevant memory location has to be burned with 00h ..
and so on ..
Rgds,
IanP