August 27, 1998
GENERAL RELEASE SPECIFICATION
The OSCS bit enables the OSC1 and OSC2 pins for external oscillator connec-
tion. OSC1 replaces PB2/CS0 and OSC2 replaces PB3/CS1. This is selected by a
mask option on the MC68HC05SB7 device.
A.5 BOOTLOADER MODE
Bootloader mode is entered upon the rising edge of RESET if IRQ/V pin is at
PP
V
and PB1/TCAP at V . The Bootloader program is masked in the ROM area
TST
DD
from $1E00 to $1FEF. This program handles copying of user code from an exter-
nal EPROM into the on-chip EPROM. The bootload function has to be done from
an external EPROM. The bootloader performs one programming pass at 1ms per
byte then does a verify pass.
A.6 EPROM PROGRAMMING
This section describes how to program the 6160-byte EPROM and the EPROM
security bit.
In packages with no quartz window, the EPROM functions as one-time program-
mable ROM (OTPROM)
Programming the on-chip EPROM is achieved by using the Program Control Reg-
ister located at address $001E.
The programming software copies to the 6144-byte space located at EPROM
addresses $0600 – $1DFF and to the 16-byte space at addresses $1FF0 – $1FFF
which includes the mask option register (MOR) at address $002F.
Please contact Motorola for programming board availability.
A.6.1 EPROM Programming Register (EPROG)
The EPROM programming register shown in Figure A-3 contains the control bits
for programming the EPROM and MOR. In normal operation, the EPROM pro-
gramming register is a read-only register that contains all logic zeros.
BIT 7
0
BIT 6
0
BIT 5
0
BIT 4
0
BIT 3
0
BIT 2
ELAT
0
BIT 1
MPGM
0
BIT 0
EPGM
0
EPROG
$001C
R
W
reset:
0
0
0
0
0
UNIMPLEMENTED
RESERVED FOR TEST
Figure A-3. EPROM Programming Register (EPROG)
EPGM — EPROM Programming
This read/write bit applies the voltage from the IRQ/V pin to the EPROM. To
PP
write the EPGM bit, the ELAT bit must already be set. Clearing the ELAT bit
also clears the EPGM bit. Reset clears EPGM.
1 = EPROM programming power switched on.
0 = EPROM programming power switched off.
MC68HC05SB7
REV 2.1
MOTOROLA
A-3
FREESCALE [ Freescale ]
