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16-27
PROGRAMMING THE NONVOLATILE MEMORY
16.9.2 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 16-6 on page 16-18). 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.
16.9.3 Auto Programming Routine
Figure 16-13 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.
Table 16-11. 8XC196MC/MD Auto Programming Memory Map
Address
Output from
8XC196MC,
8XC196MD
Internal
OTPROM
Address
Address Using
Circuit in
Figure 16-12
(A15:0)
Description
4014H N/A 14H Programming pulse width (PPW) LSB.
4015H N/A 15H Programming pulse width (PPW) MSB.
4020–402FH 2020–202FH 0020–002FH Security key for verification.
4000–7FFFH 2000–5FFFH 4000–7FFFH Code, data, and reserved locations.
Table 16-12. 8XC196MH Auto Programming Memory Map
Address
Output from
8XC196MH
Internal
OTPROM
Address
Address Using
Circuit in
Figure 16-12
(P1.3:0, A11:0)
Description
105EH N/A 105EH Programming pulse width (PPW) LSB.
105FH N/A 105FH Programming pulse width (PPW) MSB.
0020–002FH 2020–202FH 0020–002FH Security key for verification.
2000–9FFFH 2000–9FFFH 2000–9FFFH Code, data, and reserved locations.