Intel 87C196CB Chapter Memory Partitions, Memory MAP, SPECIAL-FUNCTION REGISTERS, and Windowing

CHAPTER 3

MEMORY PARTITIONS

This chapter describes the differences in the address space of the 87C196CB from that of the 8XC196NT. The 87C196CB has 56 Kbytes of one-time-programmable read-only memory (OT- PROM), while the 8XC196NT is available with 32 Kbytes. The 87C196CB also has an additional 512 bytes of register RAM.

The 87C196CB is available in either an 84-pin or a 100-pin package. The 84-pin 87C196CB, like the 8XC196NT, has up to 20 external address lines, enabling access to 1 Mbyte of linear address space. The 100-pin 87C196CB has four additional pins available for external address lines. With all 24 external address lines connected (A23:16 and AD15:0), the 100-pin 87C196CB can access 16 Mbytes of linear address space.

3.1MEMORY MAP, SPECIAL-FUNCTION REGISTERS, AND WINDOWING

Table 3-1 compares the register file addresses of the 8XC196NT and 87C196CB. Table 3-2 is a memory map of the 87C196CB. Table 3-3 lists the 87C196CB’s peripheral SFRs (these are the same as those of the 8XC196NT). Table 3-4 lists the CAN peripheral SFRs, which are unique to the 87C196CB. Tables 3-5 through 3-9 provide the information necessary to window higher memory into the lower register file for direct access.

Table 3-1. Register File Memory Addresses

Device and Hex
Address Range		Description	Addressing Modes
CB	NT
1DFF	—	Register RAM	Indirect, indexed, or windowed direct
1C00
03FF	03FF	Upper register file (register RAM)	Indirect, indexed, or windowed direct
0100	0100
00FF	00FF	Lower register file (register RAM)	Direct, indirect, or indexed
001A	001A
0019	0019	Lower register file (stack pointer)	Direct, indirect, or indexed
0018	0018
0017	0017	Lower register file (CPU SFRs)	Direct, indirect, or indexed
0000	0000

.

.

3-1