Don't know about the 27C256 but experience with 2732s was that with some manufacturers you could get away with leaving it to float whereas on others you had to explicitly pull it high (which would be my recommendation).
m On Thu, Mar 10, 2022 at 2:20 PM Stephen Adolph <[email protected]> wrote: > Quick one for the crowd. > On a 27C256, I have always thought you could ignore Vpp for normal use, > and only use it for programming. > > So, you could plug a 27C256 where the main rom lives in a T102 or T200, or > UK M100, or KC-85, or M10. whew. > > However, when I look at datasheets for 27C256, they all say normal > condition on pin 1 is VCC!!! > > What gives? > Is it ok to float pin 1, or really should we be connecting pin 1 to plus > 5V? > > thanks > Steve >
