Siemens ERTEC200 사용자 설명서

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4.2  General Purpose I/O (GPIO)  
Up to 45 General Purpose Inputs/Outputs are available in the ERTEC 200. These are divided into two groups: 
• 
GPIO[31:0] 
32 bits on the APB I/O bus 
• 
GPIO[44:32] 
13 bits as an alternative function on the LBU interface  
The GPIOs [31 : 0] can be used as follows 
• Inputs 
• Outputs 
 
• 
One of up to 3 additional special functions (Watchdog, Timer, F-Timer, UART, SPI, ETM and MC-PLL) 
 
The direction of the IO can be programmed bit-by-bit in the "GPIO_IOCTRL“ register.
 
The function selection of the special I/O functions can be programmed in the GPIO_PORT_MODE_L
 a
nd 
GPIO_PORT_MODE_H registers. 
The GPIO inputs [1 : 0] and [31 : 30] can also be used as external interrupt inputs. They are connected at the IRQ 
interrupt controller of the ARM946. The polarity of the GPIO interrupts can be specified with the  GPIO_POLSEL register 
(see GPIO register description) 
 
The following figure shows the structure of a GPIO[31 : 0] pin as a normal I/O function or as an alternative function. 
 
GPIO(i)
GPIO 
IN
GPIO
OUT (i)
Alternate function 1,2,3 (if input)
Alternate function 1,2,3 (if output)
GPIO
IOCTRL(i)
GPIO_PORT
MODE_L&..._H
(2*i+1, 2*i)
Pin  of 
ERTEC200
 
 
Figure 4: GPIO Cell on GPIO Port [31:0] of the ERTEC 200 
The GPIOs [44 : 32] are available on the LBU bus when the LBU interface is not used. The selection is made with the 
configuration pin CONFIG[2] = 1.  The GPIOs[44:32] can then be used as normal inputs or outputs. The direction of the 
GPIOs[44:32] can be programmed bit-by-bit in the "GPIO_IOCTRL2“ register.
 
 
 
 
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ERTEC 200 Manual 
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