Technologic Systems TS-5500, Руководство пользователя

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TS-5500 User’s Manual Technologic Systems
10/31/03 20
When using the Linux OS, we provide a driver to initialize and “feed” the WDT. We also provide a Linux
sample application program with full source.
If using DOS, the following sample of Turbo C code (real-mode DOS) will enable the WDT with a 4
second timeout period :
int main() {
unsigned int far *wdtctrl ;
wdtctrl = (unsigned int far *) MK_FP (0XDF00, 0X0CB0);
*wdtctrl = 0x3333;
*wdtctrl = 0xCCCC;
*wdtctrl = 0xD010 ; /* 0xD0 = Enable WDT to Reset Mode, 0x10 = 4 second timeout */
printf (“System will reset in 4 seconds”);
return 0;
}
15 LED, Jumpers and Reset Button
The TS-5500 has an LED available for user software. The user LED may be used for diagnostics,
status messages, and simple output. This signal is also available as a digital output on the DIO2 port.
When power is first supplied to the TS-5500, the user LED is immediately turned on under hardware
control. Once the processor begins execution, the LED is turned off, then flashed on and off again
briefly. After boot, this LED can be used for user applications. The state of the LED is complemented by
any activity to the Compact Flash card. (accesses to the CF causes the LED to flicker)
If the user LED does not turn on at all when power is applied, the most likely problem is the power
supply. Check that the +5V and GND connections are not reversed. A diode protects the board against
damage in such a situation.
It is preferred to use BIOS interrupt functions to interface software with the user LED and option
jumpers. Please see Appendix F for further details and the utility disk for example code.
The LED can be also accessed at I/O location 77h bit 0. A Logic “1” is LED on condition.
The CF activity signal is exclusive ORed with the control bit at I/O location 77h. This causes the LED to
always flicker when there is access to the CF card.
The reset button is connected in parallel with the external reset pin on the DIO connector. Pressing this
button will cause a hardware reset. The system will perform a ‘cold’ boot.
Jumper Function
JP1
Automatic CMOS - CMOS memory is reset every time the system boots, IDE0 and IDE2
Compact Flash are automatically detected and configured in the BIOS Configuration menu.
JP2 Enable Serial Console - Default to COM2. (unless JP6 installed)
JP3 Write Enable Drive A – Remove this jumper to write protect flash drive A:
JP4 Fast Console - Console is set to 115K baud. (defaults to 9600 baud)
JP5 User Jumper - Read using BIOS call or directly in I/O space. (See appendix D & E)
JP6 Console on COM1 (requires JP2 installed to enable console)
Table 7 - Jumper Listing