DS87C550 Datasheet, PDF (33/50 Pages) Dallas Semiconductor – EPROM High-Speed Micro with A/D and PWM

DS87C550
OTHER EPROM OPTIONS
The DS87C550 has user-selectable options that must be set before beginning software execution. These
options use EPROM bits rather than SFRs.
The EPROM selectable options may be programmed as shown in Table 10. The Option Register sets or
reads these selections. The bits in the Option Register have the following function:
Bit 7 -4
Bit 3
Bit 2-0
Reserved. Program to a 1.
Watchdog POR default. Set to 1:
Watchdog reset function is disabled on power-up. Set to 0: Watchdog reset function is
enabled automatically.
Reserved. Program to a 1.
SIGNATURE
The Signature bytes identify the product and programming revision to EPROM programmers. This
information is located at programming addresses 30h, 31h, and 60h. This information is as follows:
Address
30h
31h
60h
Value
DAh
55
00
Meaning
Manufacturer
Model
Extension
EPROM PROGRAMMING CONFIGURATION Figure 5
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