"Dave" wrote in message
...
| I bought a Pitney Bowes A510 digital scale on Ebay originally just to
| use it for weighing shipments to calculate by hand what the postage
| should be (goes up to 10 pounds in 0.1oz increments).
|
| However this scale has a built in price calculator - it'll show what
| the $$ should be to ship something. Problem is the rates are not
| updated ( for example first class 1 oz is $0.33 instead of $0.37). It
| would be nice to use this function.
|
| Rates are stored on a pluggable card containing a 27c64 ROM chip.
| I've dumped the code, looked at it in a hex editor but don't know what
| bytes to change, where the checksum is stored, etc.
|
| Anyone have a current hexdump of the rate prom from a Pitney Bowes
| A510 or similar scale? Or know how the data is arranged so I know
| what bytes to change to update to the current postage rate?

You can't buy the upgrade chip?

If I had to do this, I would substitute an sram chip configured to look like
the eprom, then try changing bytes and see what affects what. Pain to do,
but unless you can analyse the rest of the system I see no other way to do
it.

N