C509-L_97 SIEMENS [Siemens Semiconductor Group], C509-L_97 Datasheet - Page 37

• Manufacturer Part Number: C509-L_97
• Description: 8-Bit CMOS Microcontroller
• Manufacturer: SIEMENS [Siemens Semiconductor Group]

3.4.7 Operating Mode (Chipmode) Selection
The chipmode selection can be done by hardware after an active RESET or HWPD signal. Further,
the logic state of pin PRGEN is used for hardware selection. Bit Swap is not affected by hardware
selection. The chipmodes can also be selected by software. Software selection is achieved by
programming specific bits of SFR SYSCON1.
The following table 3-2 shows the hardware and software selection capabilities of the chipmodes.
Table 3-2
Hardware and Software Selection of Chipmodes
Operating Mode
(Chipmode)
Normal Mode
XRAM Mode
Bootstrap Mode
Programming Mode
Figure 3-7 below shows the information of table 3-2 as a state diagram (reference number in the
circle).
Figure 3-7
State Diagram of Chipmode Selection
Semiconductor Group
PRGEN1, SWAP = 0,1
XRAM Mode
6
4
5
Hardware Selection
PRGEN pin = low
RESET or HWPD:
from Programming Mode:
setting PRGEN pin = low
PRGEN pin = high
RESET or HWPD:
not possible
5
5
3
1
2
PRGEN1, SWAP = 0,0
PRGEN1, SWAP = 1,0
Bootstrap Mode
Normal Mode
4
3-12
6
7
edge
edge
2
1
3
4
7
Software Selection
PRGEN pin = don’t care;
setting bits PRGEN1,SWAP = 0,0;
executing unlock sequence
PRGEN pin = don’t care;
setting bits PRGEN1,SWAP = 0,1;
executing unlock sequence
PRGEN pin = high;
setting bits PRGEN1,SWAP =1,0;
executing unlock sequence
PRGEN pin = high;
setting bits PRGEN1,SWAP = 1,1;
executing unlock sequence
7
6
Memory Organization
PRGEN1, SWAP = 1,1
Programming Mode
Hardware Selection
Software Selection
MCD02645
1997-10-01
C509-L
4
5
6
7