Eprom Access Time Control Register - Motorola MVME162FX Programmer's Reference Manual

EPROM Access Time Control Register

The MVME162FX is populated with a 150ns EPROM memory
device. Due to the wide range of EPROM speeds, the contents can
be changed by software to adjust for a specific speed.
ADR/SIZ
BIT 23
NAME
OPER R
RESET 0
ET2-ET0
ROM0
$FFF42040 (8 bits)
22 21 20
ROM0
R R R/W
0 0 1 PL
EPROM access time is controlled by the state of
ET2-ET0. The following table defines the ET2-ET0
encodings.
EPROM ACCESS <= N
ET2-ET0 at 25 MHz where N =
$0 60 ns
$1 100 ns
$2 140 ns
$3 180 ns
$4 220 ns
$5 260 ns
$6 300 ns
$7 340 ns
Refer to Table 1-2.
Chapter 1.
Programming Model
19 18 17
ET2 ET1
R R/W R/W
0 1 PL 1 PL
EPROM ACCESS <= N
at 32 MHz where N =
100 ns
130 ns
160 ns
190 ns
210 ns
240 ns
Local Bus Memory Map, Note 1, in
16
ET0
R/W
1 PL
40 ns
70 ns
3-41
3