# 16V8 for Rack8 proof-of-concept test memory

# If A13 is low we access EPROM, if high we access RAM. It's that simple.

device 16v8

input
    pint:6,        # True if we are processing an interrupt
    mer.L:4,       # True if the CPU is doing a memory read
    mew.L:5,       # True if the CPU is doing a memory write
    A13.H:8,       # The high address bit

output
    e_read.L:17,     # True if we are reading from eprom
    r_sel.L:19,      # True if we are reading or writing ram
    r_write.L:18,    # True if we are writing ram

implementation

e_read  equ  !pint & mer & !A13
r_write equ  mew & A13
r_sel   equ  ((mer & !pint) | mew) & A13