Z86C34 Datasheet, PDF (53/70 Pages) Zilog, Inc. – CMOS Z8 MCUs WITH ASCI UART OFFER EFFICIENT, COST-EFFECTIVE DESIGN FLEXIBILITY

ZiLOG
Z86C34/C35/C36/C44/C45/C46
CMOS Z8® MCUs with ASCI UART
ASCI TIME CONSTANT REGISTER (ASTL)
(%(A)06H: READ/WRITE)
Table 24. ASTL Register Bit Functions
Bit
7
6
5
4
3
2
1
0
R
ASCI Time Constant Low
W
Reset
1
1
1
1
1
1
1
1
ASCI TIME CONSTANT REGISTER (ASTH)
(%(A)07H: READ/WRITE)
Table 25. ASTH Register Bit Functions
Bit
7
6
5
4
3
2
1
0
R
ASCI Time Constant High
W
Reset
1
1
1
1
1
1
1
1
The ASTL and ASTH registers are only used when the BRG
mode bit in the ASEXT register is set to a 1. These two 8-
bit registers form a 16-bit counter with a flip-flop logic cir-
cuit (DIVIDE-BY-2) on the output so that the final BRG out-
put is symmetrical. The values written to these registers de-
termine the time constant from which the baud rate is
generated.
DS007601-Z8X0499
PRELIMINARY
53