Отправлено Titanic 24 сентября 2003 г. 15:20

Не могу заставить порт G работать обычном режиме.
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MCUCR:=0;

PortG:= %00011111;
DDRG := %00011111;

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PortG:= %00011111;
PortG:= %00000000;

А на выходах PG2(ALE)=0, PG1(RD)=1, PG0(WE)=1, PG3=1, PG4=???

Или я снова не туда смотрю.... :((

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MCU Control Register –
MCUCR
• Bit 7 – SRE: External SRAM/XMEM Enable
Bit 7 6 5 4 3 2 1 0
SRE SRW10 SE SM1 SM0 SM2 IVSEL IVCE MCUCR
Read/Write R/W R/W R/W R/W R/W R/W R/W R/W
Initial Value 0 0 0 0 0 0 0 0

Writing SRE to one enables the External Memory Interface.The pin functions AD7:0,
A15:8, ALE, WR, and RD are activated as the alternate pin functions. The SRE bit overrides
any pin direction settings in the respective data direction registers. Writing SRE to
zero, disables the External Memory Interface and the normal pin and data direction settings
are used.
• Bit 6 – SRW10: Wait State Select Bit
For a detailed description in non ATmega103 compatibility mode, see common description
for the SRWn bits below (XMRA description). In ATmega103 compatibility mode,
writing SRW10 to one enables the wait state and one extra cycle is added during
read/write strobe as shown in Figure 14.

• Собственно говоря - он и так отключен (если установить SRE сразу отребается и порт C...)... но как заставить порт G работать на выход? — Titanic   (24.09.2003 16:00, пустое)