MC68HC705P6A Datasheet, PDF (85/130 Pages) Motorola, Inc – HCMOS Microcontroller Unit

EPROM
EPROM Programming Register (EPROG)
Address $001C
Bit 7
6
5
4
3
2
1
Bit 0
Read: 0
0
0
0
0
0
ELAT
EPGM
Write:
Reset: 0
0
0
0
0
0
0
0
= Unimplemented
Figure 10-1. EPROM Programming Register (EPROG)
EPGM — EPROM Program Control
If the EPGM bit is set, programming power is applied to the EPROM
array. If the EPGM bit is cleared, programming power is removed from
the EPROM array. The EPGM bit cannot be set unless the ELAT bit
is set already.
Whenever the ELAT bit is cleared, the EPGM bit is cleared also. Both
the EPGM and the ELAT bit cannot be set using the same write
instruction. Any attempt to set both the EPGM and ELAT bit on the
same write instruction cycle will result in the ELAT bit being set and
the EPGM bit being cleared. The EPGM bit is a read-write bit and can
be read at any time. The EPGM bit is cleared by reset.
ELAT— EPROM Latch Control
If the ELAT bit is set, the EPROM address and data bus are
configured for programming to the array. If the ELAT bit is cleared, the
EPROM address and data bus are configured for normal reading of
data from the array. When the ELAT bit is set, the address and data
bus are latched in the EPROM array when a subsequent write to the
array is made. Data in the EPROM array cannot be read if the ELAT
bit is set.
Whenever the ELAT bit is cleared, the EPGM bit is cleared also. Both
the EPGM and the ELAT bit cannot be set using the same write
instruction. Any attempt to set both the EPGM and ELAT bit on the
same write instruction cycle will result in the ELAT bit being set and
the EPGM bit being cleared. The ELAT bit is a read-write bit and can
be read at any time. The ELAT bit is cleared by reset.
MC68HC705P6A — Rev. 2.0
MOTOROLA
EPROM
Advance Information
85