Z87100 Datasheet, PDF (27/48 Pages) Zilog, Inc. – Wireless Transmitter

Zilog
Z87100
Wireless Transmitter
Table 6. Data and PN Clock Configuration
DATA_CLOCKMODE
0
0
0
0
0
0
0
0
1
DCLK
xxxxx000
xxxxx001
xxxxx010
xxxxx011
xxxxx100
xxxxx101
xxxxx110
xxxxx111
DCLK
PNCLK
refclk
refclk
refclk
refclk
refclk/4
refclk/4
refclk/4
refclk/4
refclk
DATACLK
pnclk/PNLEN
3
pnclk/(PNLENx2)
pnclk/(PNLENx4)
pnclk/(PNLENx8)
4xpnclk/PNLEN
2xpnclk/PNLEN
pnclk/PNLEN
pnclk/(PNLENx2)
pnclk/DCLK
Time Base Generator. The time base generator can be
used while the Z8 is in stop mode to initiate a stop-mode
recovery or while the Z8 is operating to generate IRQ0 in-
terrupts as a time-keeping pulse. If used while the Z8 is in
stop mode, time-out will trigger a stop-mode recovery
("warm start") and reset the processor to address 000C
(hex). Otherwise, time-out of the time base generator will
set IRQ0 to 1. This mode can be used while the Z8 contin-
ues operation and a regular time base is desired, where
IRQ0 can either be polled as a flag and manually cleared
by the user or enabled as an interrupt and automatically
cleared. The time base generator is programmable and
can provide clock signals every .25 seconds, one second,
one minute, or one hour, with control of the time base gen-
erator provided through the TMBASE register at %(C)06.
TMBASE
The time base generator control register, located at
%(C)06 and depicted in Figure 18, allows the time base to
be selected and its actions controlled.
TIMEOUT_SELECT. (TMBASE D0-D1) determines the
time base. A value of D1=0, D0=0 selects .25 seconds; 01
selects one second; 10 selects one minute; and 11 selects
one hour.
TIMEOUT_ENABLE. (TMBASE D2) enables and disables
the time base generator. When set to 0,
TIMEOUT_ENABLE stops current operation of the time
base generator. When set to 1, TIMEOUT_ENABLE re-
sets and starts the time base generator. Reading
TIMEOUT_ENABLE provides an indication of the time
base generator's status: if set to 0, the time base generator
is off; if set to 1, the generator is currently operating.
CLOCK_SELECT. (TMBASE D3) selects either RC or
TMBASE as the clock for the Z8. If set to 0, RC will be the
clock for the Z87100; if set to 1, TMBASE will be the clock.
Determination of which clock is used upon Power-On Re-
set ("cold start") is mask-programmable, to be selected by
the customer at the time ROM code is submitted. Upon a
Stop-Mode Recovery warm start, however, the value of
this bit (as is true for all the values of this register) is not
reset. As a result, a customer could, for example, mask-
program the Z87100 to power-up using RC and then, un-
der software control, switch. Depending on the application,
operation during the wake cycle could then be conducted
using either RC or TMBASE.
If the external time base clock input is not connected to an
external clock source, pin 10 should be connected to
ground.
DS96WRL0700
PRELIMINARY
3-27