Z80180/Z8S180/Z8L180
Enhanced Z180 Microprocessor
Zilog
IOA7, 6: I/O Address Relocation (bits 7,6). IOA7 and
IOA6 relocate internal I/O as shown in Figure 85. Note that
the high-order 8 bits of 16-bit internal I/O address are al-
ways 0. IOA7 and IOA6 are cleared to 0 during Reset.
1
00FFH
IOA7-IOA6 = 1 1
IOA7-IOA6 = 1 0
IOA7- IOA6 = 0 1
IOA7-IOA6 = 0 0
00COH
00BFH
008OH
007OH
004OH
003FH
000OH
Figure 85. I/O Address Relocation
IOSTP. IOSTOP Mode (bit 5). IOSTOP mode is enabled
when IOSTP is set to 1. Normal I/O operation resumes
when IOSTOP is reprogrammed or Reset to 0
DS971800401
P R E L I M I N A R Y
1-65
ZILOG [ ZILOG, INC. ]
