Operations For Selecting Memory Access Mode - Fujitsu MB90895 Series Hardware Manual

3.9.4

Operations for Selecting Memory Access Mode

This section explains selection of the memory access mode in the reset sequence.
I Operations for Selecting Memory Access Mode
After reset is cancelled, the CPU selects the memory access mode according to the procedure shown in
Figure 3.9-5 by referencing the settings of the mode pins and mode data.
Check the mode pin
Reset factor cancellation wait
oscillation stabilization time)
Check the mode data
Figure 3.9-5 Operations for Selecting Memory Access Mode
(external reset or
Mode fetched
M1,M0="00
Generate the reset factor
Setting of mode pin
(MD2,1,0)?
Internal data read to
internal ROM.
All I/O pins are
High-Z.
During reset
operation?
NO
Fetch the mode data and reset
vectors from internal ROM
"
M1 and M0 bit
B
of mode data
Setting the single
chip mode
CHAPTER 3 CPU
YES
157