C501_1 Datasheet, PDF (94/121 Pages) Siemens Semiconductor Group – 8-Bit Single-Chip Microcontroller

OTP Memory Operation
C501
9 OTP Memory Operation of the C501-1E
The C501-1E is the OTP version of the C501-1R ROM version microcontroller. Its functionality is
fully compatible with the C501-1R functionality. This chapter describes in detail the programming
features of the C501-1E.
9.1 Programming Modes
The C501-1E is programmed by usng a modified Quick-Pulse Programming^{TM 1)} algorithm. It differs
from older methods in the value used for V_PP (programming supply voltage) and in the width and
number of the ALE/PROG pulses. The C501-1E contains two signature bytes that can be read and
used by a programming system to identify the device. The signature bytes identify the manufacturer
and the type of the device.
Table 9-11 shows the logic levels for reading the signature byte, and for programming the program
memory, the encryption table, and the security bits.
Table 9-11
OTP Programming Modes
Mode
RESET PSEN
Read signature
1
0
Program code data
1
0
Verify code data
1
0
Progam encryption table 1
0
Program security bit 1
1
0
Program security bit 2
1
0
ALE/
PROG
1
0
1
0
0
0
EA/V_PP
1
V_PP
1
V_PP
V_PP
V_PP
P2.7
0
1
0
1
1
1
P2.6
0
0
0
0
1
1
P3.7
0
1
1
1
1
0
P3.6
0
1
1
0
1
0
Notes :
1. “0” = valid low for that pin, “1” = valid high for that pin.
2. V_PP = 12.75 V ± 0.25V
3. V_CC = 5 V ± 10% during programming and verification.
4. ALE/PROG receives 25 programming pulses while V_PP is held at 12.75 V. Each programming pulse is low for
100 µs (± 10 µs) and high for a minimum of 10 µs.
1 _{Quick-Pulse Programming}TM _{is a trademark phrase of Intel Corporation}
Semiconductor Group
9-1