Operating Environment; Auto Programming Routine - Intel 8XC196NT User Manual

Address
Output from Internal
8XC196 OTPROM
Device Address
(A15:0)
4014H
4015H
4020–402FH FF2020–FF202FH
4000–7FFFH FF2000–FF9FFFH

15.9.2 Operating Environment

In the auto programming mode, the PCCBs are loaded into the chip configuration registers. Since
the device gets programming data through the external bus, the memory device in the program-
ming system must correspond to the default configuration (Figure 15-6 on page 15-18). Auto pro-
gramming requires an 8-bit bus configuration, so the circuit must tie the BUSWIDTH pin low.
The PCCB defaults allow you to use any standard EPROM that satisfies the AC specifications
listed in the device datasheet.
The auto programming mode also loads CCB0 into an internal RAM location and checks the lock
bits. If either lock bit is programmed, the auto programming routine compares the internal secu-
rity key to the external security key location. If the verification fails, the device enters an endless
internal loop. If the security keys match, the routine continues. The auto programming routine
uses the modified quick-pulse algorithm and the pulse width value programmed into the external
EPROM (locations 14H and 15H).

15.9.3 Auto Programming Routine

Figure 15-13 illustrates the auto programming routine. This routine checks the security lock bits
in CCB0; if either bit is programmed, it compares the internal security key to the external security
key locations. If the security keys match, the routine continues; otherwise, the device enters an
endless loop.
PROGRAMMING THE NONVOLATILE MEMORY
Table 15-10. Auto Programming Memory Map
Address
Using Circuit
in Figure
15-12
(P1.2:1, A13:0)
N/A
N/A
0020–002FH Security key for verification.
4000–BFFFH Code, data, and reserved locations.
Description
14H Programming pulse width (PPW) LSB.
15H Programming pulse width (PPW) MSB.
15-27