Motorola DSP56301 - Manual (Page 332)

Programming Sheets
B -20 DSP56301 User’s Manual
Figure B-8. Address Attribute Registers (AAR[3–0])
Bus Interface Unit
Address Attribute Registers 3 (AAR3)
Reset = $000000
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 19 18 17 16 23 22 21 20
* = Reserved, Program as 0
0 = Disable AA pin and logic during
1 = Enable AA pin and logic during
Bus Packing Enable, Bit 7
0 = Disable internal packing/unpacking logic
*
0
Bus Access Type, Bits 1–0
Bus Y Data Memory Enable, Bit 5
1 = Enable internal packing/unpacking logic
Bus Number of Address Bits to Compare, Bits 11–8
BNC[3–0] = number of bits (from BAC bits) that are
Bus Address to Compare, Bits 23–12
BAC[11–0] = address to compare to the
BAC11
(Combinations BNC[3–0] = 1111, 1110, 1101 are
reserved.)
external Y data space accesses
external Y data space accesses
0 = Disable AA pin and logic during
1 = Enable AA pin and logic during
Bus X Data Memory Enable, Bit 4
external X data space accesses
external X data space accesses
0 = Disable AA pin and logic during
1 = Enable AA pin and logic during
Bus Program Memory Enable, Bit 3
external program space accesses
external program space accesses
Bus Address Attribute Polarity, Bit 2
0 = AA/RAS signal is active low
1 = AA/RAS signal is active high
BAT[1–0] Encoding
00 Reserved
01 SRAM access
10 DRAM access
11 Reserved
compared to the external address
external address in order to decide
whether to assert the AA pin
Application: Date:
Programmer:
Sheet 3 of 3
BAC10 BAC9 BAC8 BAC7 BAC6 BAC5 BAC4 BAC3 BAC2 BAC1 BAC0 BNC3 BNC2 BNC1 BNC0 BAC7 BYEN BXEN BPEN BAAP BAT1 BAT0
X:$FFFFF6 Read/Write
Address Attribute Registers 2 (AAR2) X:$FFFFF7 Read/Write
Address Attribute Registers 1 (AAR1) X:$FFFFF8 Read/Write
Address Attribute Registers 0 (AAR0) X:$FFFFF9 Read/Write