SAB-C509-LM SIEMENS [Siemens Semiconductor Group], SAB-C509-LM Datasheet - Page 20

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

C509-L
Bootstrap Mode Configuration
In the Bootstrap Mode the Boot ROM and the external FLASH/ROM/EPROM are mapped into the
code memory area. 61K byte external SRAM as well as 3K byte internal data memory (XRAM) are
provided in the external data memory area. The external program memory is controlled by the
PSEN/RDF signal. Read and write accesses to the external data memory are controlled by the RD
and WR pins of port 3.
Figure 8
Locations of Code- and Data Memory in Bootstrap Mode
Semiconductor Group
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