W79E217A Datasheet, PDF (27/207 Pages) Winbond – 8-bit Microcontroller

Preliminary W79E217A Data Sheet
TIMER 0 MSB
Bit:
7
6
5
4
3
2
1
0
TH0.7
TH0.6
TH0.5
TH0.4
TH0.3
TH0.2
TH0.1
TH0.0
Mnemonic: TH0
TH0.7-0
Timer 0 MSB
Address: 8Ch
TIMER 1 MSB
Bit:
7
6
5
4
3
2
1
0
TH1.7
TH1.6
TH1.5
TH1.4
TH1.3
TH1.2
TH1.1
TH1.0
Mnemonic: TH1
TH1.7-0
Timer 1 MSB
Address: 8Dh
CLOCK CONTROL
Bit:
7
6
5
4
3
2
1
0
WD1
WD0
T2M
T1M
T0M
MD2
MD1
MD0
Mnemonic: CKCON
Address: 8Eh
BIT NAME
FUNCTION
7 WD1 Watchdog Timer mode select bit 1. See table below.
6 WD0 Watchdog Timer mode select bit 0. See table below.
Timer 2 clock select:
5 T2M 1: divide-by-4 clock.
0: divide-by-12 clock.
Timer 1 clock select:
4 T1M 1: divide-by-4 clock.
0: divide-by-12 clock.
Timer 0 clock select:
3 T0M 1: divide-by-4 clock.
0: divide-by-12 clock.
Stretch MOVX select bit 2:
MD2, MD1, and MD0 select the stretch value for the MOVX instruction. The RD or
WR strobe is stretched by the selected interval, which enables the device to access
2 MD2 _{faster or slower external memory devices or peripherals without the need for}
external circuits. By default, the stretch value is one. See table below.
(Note: When accessing on-chip SRAM, these bits have no effect, and the MOVX
instruction always takes two machine cycles.)
1 MD1 Stretch MOVX select bit 1. See MD2.
0 MD0 Stretch MOVX select bit 0. See MD2.
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Publication Release Date: December 14, 2007
Revision A3.0