MEMORY PARTITIONS

4.2.1Selecting a Window

The window selection register (Figure 4-3) selects a window to be mapped into the top of the low- er register file.

Table 4-9 provides a quick reference of WSR values for windowing the peripheral SFRs. Table 4-10 on page 4-14 lists the WSR values for windowing the upper register file.

WSR

Address:

0014H

 

Reset State:

00H

The window selection register (WSR) maps sections of RAM into the top of the lower register file, in 32-, 64-, or 128-byte increments. PUSHA saves this register on the stack and POPA restores it.

7

 

 

 

 

 

 

 

 

 

0

W6

W5

W4

 

W3

 

W2

W1

 

W0

 

 

 

 

 

 

 

 

 

 

 

Bit

Bit

 

 

 

Function

 

 

 

 

Number

Mnemonic

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

7

Reserved; for compatibility with future devices, write zero to this bit.

 

 

 

 

 

 

 

 

 

 

 

6:0

W6:0

Window Selection

 

 

 

 

 

 

 

 

 

These bits specify the window size and number. See Table 4-9 on page

 

 

4-13 or Table 4-10 on page 4-14. See Table 4-9 for peripheral SFR windows

 

 

or Table 4-10 for upper register file windows.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Figure 4-3. Window Selection (WSR) Register

Table 4-9. Selecting a Window of Peripheral SFRs

 

 

 

WSR Value for

WSR Value for

WSR Value for

 

 

Peripherals

32-byte Window

64-byte Window

128-byte Window

 

 

 

(00E0–00FFH)

(00C0–00FFH)

(0080–00FFH)

 

 

 

 

 

 

Port 2

 

 

 

 

Waveform generator

7EH

3FH

 

 

Port 7 (MD only)

 

 

 

 

Peripheral interrupts

 

 

 

 

Pulse-width modulator

 

 

1FH

 

A/D converter

7DH

 

 

 

 

 

Frequency generator (MD only)

 

3EH

 

 

Reset control (MH only)

 

 

 

 

Port 1 (MH only)

7CH

 

 

 

Serial I/O port (MH only)

 

 

 

 

 

 

 

Timer 1–2

 

 

 

 

EPA compare 2–3 (MC)

7BH

 

 

 

EPA compare 0–5 (MD)

 

 

 

 

 

 

 

EPA compare 0–2 (MH)

 

 

 

 

EPA capture/compare 0–3 (MC)

 

3DH

1EH

 

EPA compare 0–1 (MC)

 

 

 

 

EPA capture/compare 0–5 (MD)

7AH

 

 

 

EPA capture/compare 0–1 (MH)

 

 

 

 

EPA compare 3 (MH)

 

 

 

 

 

 

 

 

4-13

 

 

 

 

 

 

 

 

 

 

 

Page 78
Image 78
Intel 8XC196MD, 8XC196MH, 8XC196MC manual Selecting a Window, Wsr, Bit Function Number, WSR Value for Peripherals