TS80C54X2-LIB View Datasheet(PDF) - Atmel Corporation
Part Name
Description
Manufacturer
TS80C54X2-LIB Datasheet PDF : 58 Pages
| |||
TS80C54X2/C58X2
TS87C54X2/C58X2
6.11 Reduced EMI Mode
The ALE signal is used to demultiplex address and data buses on port 0 when used with external program or data
memory. Nevertheless, during internal code execution, ALE signal is still generated. In order to reduce EMI, ALE
signal can be disabled by setting AO bit.
The AO bit is located in AUXR register at bit location 0. As soon as AO is set, ALE is no longer output but
remains active during MOVX and MOVC instructions and external fetches. During ALE disabling, ALE pin is
weakly pulled high.
Table 19. AUXR Register
AUXR - Auxiliary Register (8Eh)
7
6
5
4
3
2
1
0
-
-
-
-
-
-
RESERVED
AO
Bit
Number
7
6
5
4
3
2
1
0
Bit
Mnemonic
Description
-
Reserved
The value read from this bit is indeterminate. Do not set this bit.
-
Reserved
The value read from this bit is indeterminate. Do not set this bit.
-
Reserved
The value read from this bit is indeterminate. Do not set this bit.
-
Reserved
The value read from this bit is indeterminate. Do not set this bit.
-
Reserved
The value read from this bit is indeterminate. Do not set this bit.
-
Reserved
The value read from this bit is indeterminate. Do not set this bit.
This bit must be set for normal operation
RESERVED
For ALE disabling, program 03H in AUXR register.
For standard operation, program 02H in AUXR register.
ALE Output bit
AO
Clear to restore ALE operation during internal fetches.
Set to disable ALE operation during internal fetches.
Reset Value = XXXX XX00b
Not bit addressable
34
Rev. C - 15 January, 2001
Share Link: 