![Rabbit Rabbit 4000 User Manual Download Page 85](http://html1.mh-extra.com/html/rabbit/rabbit-4000/rabbit-4000_user-manual_3116714085.webp)
75
8.4 Register Descriptions
Parallel Port A Data Register
(PADR)
(Address = 0x0030)
Bit(s)
Value
Description
7:0
Read
The current state of Parallel Port A pins PA7–PA0 is reported.
Write
The Parallel Port A buffer is written with this value for transfer to the Parallel
Port A output register on the next rising edge of the peripheral clock.
Slave Port Control Register
(SPCR)
(Address = 0x0024)
Bit(s)
Value
Description
7
0
Program fetch as a function of the SMODE pins.
1
Ignore the SMODE pins program fetch function.
6:5
read
These bits report the state of the SMODE pins.
write
These bits are ignored and should be written with zero.
4:2
000
Disable the slave port. Parallel Port A is a byte-wide input port.
001
Disable the slave port. Parallel Port A is a byte-wide output port.
010
Enable the slave port, with /SCS from Parallel Port E bit 7.
011
Enable the auxiliary I/O bus. Parallel Port A is used for the data bus and Parallel
Port B[7:2] is used for the address bus.
100
This bit combination is reserved and should not be used.
101
This bit combination is reserved and should not be used.
110
Enable the slave port, with /SCS from Parallel Port B bit 6.
111
Enable the auxiliary I/O bus. Parallel Port A is used for the data bus and Parallel
Port B[7:0] is used for the address bus.
1:0
00
Slave port interrupts are disabled.
01
Slave port interrupts use Interrupt Priority 1.
10
Slave port interrupts use Interrupt Priority 2.
11
Slave port interrupts use Interrupt Priority 3.
Summary of Contents for Rabbit 4000
Page 1: ...Rabbit 4000 Microprocessor User s Manual 019 0152 070720 H...
Page 18: ...8 Rabbit 4000 Microprocessor User s Manual...
Page 40: ...30 Rabbit 4000 Microprocessor User s Manual...
Page 74: ...64 Rabbit 4000 Microprocessor User s Manual...
Page 82: ...72 Rabbit 4000 Microprocessor User s Manual...
Page 86: ...76 Rabbit 4000 Microprocessor User s Manual...
Page 96: ...86 Rabbit 4000 Microprocessor User s Manual...
Page 182: ...172 Rabbit 4000 Microprocessor User s Manual...
Page 240: ...230 Rabbit 4000 Microprocessor User s Manual...
Page 248: ...238 Rabbit 4000 Microprocessor User s Manual...
Page 256: ...246 Rabbit 4000 Microprocessor User s Manual...
Page 310: ...300 Rabbit 4000 Microprocessor User s Manual...
Page 330: ...320 Rabbit 4000 Microprocessor User s Manual...
Page 348: ...338 Rabbit 4000 Microprocessor User s Manual...