6264 static RAM

The 6264 is an 8kB static RAM, available in 70 to 200 nanosecond access time variants. It can function on both an 8080 style bus (separate /WE and /OE strobes) or on a 6500 style bus (by grounding /OE and connecting the R/W signal to /WE)

6264 Pinout

      .----\/----.
 nc - |01      28| - +5V
A12 - |02      27| - /WE
 A7 - |03      26| - CS2
 A6 - |04      25| - A8
 A5 - |05      24| - A9
 A4 - |06      23| - A11
 A3 - |07      22| - /OE
 A2 - |08      21| - A10
 A1 - |09      20| - /CS1
 A0 - |10      19| - D7
 D0 - |11      18| - D6
 D1 - |12      17| - D5
 D2 - |13      16| - D4
GND - |14      15| - D3
      `----------'

Signal descriptions

A0-A12

address

D0-D7

data

/CS1 and CS2 (chip selects 1 and 2)

when /CS1 is low and CS2 is high, the chip is selected and will accept input or provide output to the data bus.

/WE (write enable)

When the chip is selected, if this pin is low, the eight-bit data D will be written to the address inside the RAM specified by A

/OE (output enable)

When the chip is selected, if this pin is low and /WE is high, the eight bit data in the RAM at address A will be output onto the pins D.

The difference between /OE and the chip selects is that the 6264 responds much faster to /OE, but it draws less power when the chip selects are deasserted.

See also

• PRG RAM circuit