Intel 8XC196NP manual Data Fetches in the 1-Mbyte and 64-Kbyte Modes, 80C196NP and 80C196NU

8XC196NP, 80C196NU USER’S MANUAL

Code fetches are from external memory or internal memory, depending on the device, the mem- ory location, and the value of the EA# input.

80C196NU:

Code executes from page 0FH in external memory. (The 80C196NU has no EA# input.)

80C196NP:

For devices without internal nonvolatile memory, EA# must be tied low, and code executes only from page 0FH in external memory.

83C196NP:

Code in all locations except FF2000–FF2FFFH executes from external memory.

Instruction fetches from FF2000–FF2FFFH are controlled by the EA# input:

•If EA# is low, code executes from external memory (page 0FH).

•If EA# is high, code executes from internal ROM (page FFH).

5.5.5Data Fetches in the 1-Mbyte and 64-Kbyte Modes

Data fetches are the same in the 1-Mbyte and 64-Kbyte modes. The device can access data in any page. Data accesses to page 00H are nonextended. Data accesses to any other page are extended.

NOTE

This information on data fetches applies only for EP_REG = 00H.

80C196NP and 80C196NU:

Data accesses to the register file (0000– 03FFH) and the SFRs (1F00–1FFFH) are directed to the internal registers. All other data accesses are directed to external memory.

83C196NP:

Data accesses to the register file (0000–03FFH) and the SFRs (1F00–1FFFH) are directed to the internal registers. Accesses to other locations are directed to external memory, except as noted below:

Data accesses to FF2000–FF2FFFH depend on the EA# input:

•If EA# is low, accesses are to external memory (page 0FH).

•If EA# is high, accesses are to the internal ROM (page FFH).

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