z86e72 ZiLOG Semiconductor, z86e72 Datasheet - Page 44

• Manufacturer Part Number: z86e72
• Description: Otp Microcontroller
• Manufacturer: ZiLOG Semiconductor

PS008704-0507
The upper nibble of the register pointer
working register group of 16 bytes in the register file, out of the possible 256, is
accessed. The lower nibble selects the expanded register file bank and, in the
case of the Z86E7X family, banks 0, F, and D are implemented. A 0h in the lower
nibble allows the normal register file (bank 0) to be addressed, but any other value
from 1h to Fh exchanges the lower 16 registers to an expanded register bank.
For example, Z86E73 (see
But if:
The counter/timers are mapped into ERF group D. Access is easily done using the
following example:
R253 RP = 00H
R253 RP = 0DH
LD
LD
LD
LD
LD
R0 = Port0
R1 = Port1
R2 = Port2
R3 = Port3
R0 = CTRL0
R1 = CTRL1
R2 = CTRL2
R3 = Reserved
RP,#0Dh
R0,#xx
1,#xx
RP,#7Dh
R1,2
Figure
; Select ERF D for access and register
; Bank 0 as the working register group.
; access CTRL0
; access CTRL1
; Select expanded register group (ERF)
; group D for access and register
; Bank 7 as the working register bank.
; CTRL2→register 71H
22):
(Figure 23
on page 42) selects which
OTP Microcontroller
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