Z8E520 Datasheet, PDF (39/43 Pages) Zilog, Inc. – 1.5 MBPS USB Device Controller

Zilog
Z8E520/C520
1.5 MBPS USB Device Controller
0FD
RP
1
D7
D6 D5 D4
D3 D2
D1 D0
Register Pointer
MUST BE 0. (ONLY PAGE0 IS
IMPLEMENTED ON Z8E520.)
The upper nibble of the register file address
provided by the register pointer specifies
the active working register group.
DF
R15
Register Group D
D0
R0
CF
R15
Register Group C
C0
R0
3F
R15
Register Group 3
30
R0
2F
R15
Register Group 2 * (ACTIVE)
20
R0
1F
R15
Register Group 1
10
R0
0F
R15
Register Group 0
00
R0
* Register Group 2 is active if RP = 20H.
The lower nibble of the register
file address provided by the
instruction points to the
specific register.
Figure 26. Z8E520 Register Pointe
DS97KEY2005
PRELIMINARY
39