C505-2RM SIEMENS [Siemens Semiconductor Group], C505-2RM Datasheet - Page 52

• Manufacturer Part Number: C505-2RM
• Description: 8-Bit CMOS Microcontroller
• Manufacturer: SIEMENS [Siemens Semiconductor Group]

OTP Memory Operation (C505A and C505CA only)
The C505A/C505CA contains a 32k byte one-time programmable (OTP) program memory. With the
C505A/C505CA fast programming cycles are achieved (1 byte in 100 sec). Also several levels of
OTP memory protection can be selected.
For programming of the device, the C505A/C505CA must be put into the programming mode. This
typically is done not in-system but in a special programming hardware. In the programming mode
the C505A/C505CA operates as a slave device similar as an EPROM standalone memory device
and must be controlled with address/data information, control lines, and an external 11.5V
programming voltage. Figure 26 shows the pins of the C505A/C505CA which are required for
controlling of the OTP programming mode.
Figure 26
Programming Mode Configuration
Semiconductor Group
PALE
PMSEL0
PMSEL1
XTAL1
XTAL2
A0 - A7 /
A8 - A14
Port 2
V
CC
C505CA
C505A
52
V
SS
Port 0
MCS03637
EA /
PROG
PRD
RESET
PSEN
PSEL
D0 - D7
V
PP
C505A / C505CA
C505 / C505C
1997-12-01