Modem User Manual

46
I/O SPACE - BANK0
OFFSET NAME TYPE SYMBOL
8 MEMORY INFORMATION
REGISTER
READ ONLY MIR
HIGH
BYTE
FREE MEMORY AVAILABLE (IN BYTES * 256 * M)
0 0 0 1 1 0 0 0
LOW
BYTE
MEMORY SIZE (IN BYTES *256 * M)
0 0 0 1 1 0 0 0
FREE MEMORY AVAILABLE - This register can
be read at any time to determine the amount of
free memory. The register defaults to the
MEMORY SIZE upon reset or upon the RESET
MMU command.
MEMORY SIZE - This register can be read to
determine the total memory size, and will always
read 18H (6144 bytes) for the SMC91C95.
MEMORY SIZE
REGISTER
M ACTUAL MEMORY
SMC91C90 FFH 1 64 kbytes
SMC91C90 40H 1 16 kbytes
SMC91C92/4 12H 1 4608 bytes
SMC91C95 18H 1 6144 bytes
SMC91C100 FFH 2 128 kbytes