Operating Modes and On-Chip Memory
M68HC11E Family Data Sheet, Rev. 5.1
50
Freescale Semiconductor
MBE — Multiple-Byte Programming Enable Bit
When multiple-byte programming is enabled, address bit 5 is considered a don’t care so that bytes with
address bit 5 = 0 and address bit 5 = 1 both get programmed. MBE can be read in any mode and
always reads 0 in normal modes. MBE can be written only in special modes.
0 = EPROM array configured for normal programming
1 = Program two bytes with the same data
Bit 6 — Unimplemented
Always reads 0
ELAT — EPROM/OTPROM Latch Control Bit
When ELAT = 1, writes to EPROM cause address and data to be latched and the EPROM/OTPROM
cannot be read. ELAT can be read any time. ELAT can be written any time except when PGM = 1; then
the write to ELAT is disabled.
0 = EPROM/OTPROM address and data bus configured for normal reads
1 = EPROM/OTPROM address and data bus configured for programming
EXCOL — Select Extra Columns Bit
0 = User array selected
1 = User array is disabled and extra columns are accessed at bits [7:0]. Addresses use bits [13:5]
and bits [4:0] are don’t care. EXCOL can be read and written only in special modes and always
returns 0 in normal modes.
EXROW — Select Extra Rows Bit
0 = User array selected
1 = User array is disabled and two extra rows are available. Addresses use bits [7:0] and bits [13:8]
are don’t care. EXROW can be read and written only in special modes and always returns 0 in
normal modes.
T[1:0] — EPROM Test Mode Select Bits
These bits allow selection of either gate stress or drain stress test modes. They can be read and written
only in special modes and always read 0 in normal modes.
Address: $1036
Bit 7
654321
Bit 0
Read:
MBE
ELAT
EXCOL
EXROW
T1
T0
PGM
Write:
Reset:
00000000
= Unimplemented
Figure 2-15. MC68HC711E20 EPROM Programming
Control Register (EPROG)
T1
T0
Function Selected
0
Normal mode
01
Reserved
1
0
Gate stress
1
Drain stress