Delta Tau PMAC2A-PC/104 ユーザーズマニュアル

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PMAC2A PC104 Hardware Reference Manual 
Baseboard Hardware Setup 
CPU Jumper Configuration 
E15A-E15C:  Flash Memory Bank Select Jumpers – The flash-memory IC in location U10 on the 
PMAC2A PC/104 base board has the capacity for eight separate banks of firmware, only one of which 
can be used at any given time.  The eight combinations of settings for jumpers E15A, E15B, and E15C 
select which bank of the flash memory is used.  In the factory production process, firmware is loaded only 
into Bank 0, which is selected by having all of these jumpers OFF.  
E10-E12:  Power-Up State Jumpers – Jumper E10 must be OFF, jumper E11 must be ON, and jumper 
E12 must be ON, in order for the CPU to copy the firmware from flash memory into active RAM on power-
up/reset.  This is necessary for normal operation of the card.  (Other settings are for factory use only.) 
E14:  Watchdog Timer Jumper – Jumper E14 must be OFF for the watchdog timer to operate.  This is a 
very important safety feature, so it is vital that this jumper be OFF in normal operation.  E14 should only 
be put ON to debug problems with the watchdog timer circuit.  
W1:  Flash chip select – Jumper W1 in position 1-2 selects a 28F320J3A part for the U10 flash chip. 
Jumper W1 in position 2-3 selects a 28F320J5A part for the U10 flash chip.  This jumper is installed in 
the factory and must not be changed from its default state. 
Communication Jumpers 
E18-E19:  PC/104 Bus Base Address Control – Jumpers E18 and E19 on the PMAC2A PC/104 
baseboard determine the base address of the card in the I/O space of the host PC’s bus.  Together, they 
specify four consecutive addresses on the bus where the card can be found.  The jumpers form the base 
address in the following fashion: 
E18 
E19 
Address (hex) 
Address (dec) 
OFF OFF 
$200 
512 
OFF ON 
$210 
528 
ON OFF 
$220 
544 
ON ON 
$230 
560 
The default base address is 528 ($210) formed with jumper E18 removed and E19 installed.  This 
configuration is necessary for using the USB or Ethernet ports of the Acc-2P communications board. 
I/O Configuration Jumpers 
E16:  ADC Enable Jumper – Install E16 to enable the analog-to-digital converter circuitry ordered 
through Option-12.  Remove this jumper to disable this option, which might be necessary to control 
motor 1 through a digital amplifier with current feedback. 
Resistor Packs Configuration 
Differential or Single-Ended Encoder Selection 
The differential input signal pairs to the PMAC have user-configurable pull-up/pull-down resistor 
networks to permit the acceptance of either single-ended or differential signals in one setting, or the 
detection of lost differential signals in another setting. 
The ‘+’ inputs of each differential pair each have a hard-wired 1 k
Ω pull-up resistor to +5V.  This cannot 
be changed. 
The ‘-‘ inputs of each differential pair each have a hard-wired 2.2 k
Ω resistor to +5V; each also has 
another 2.2 k
Ω resistor as part of a socketed resistor pack that can be configured as a pull-up resistor to 
+5V, or a pull-down resistor to GND. 
If this socketed resistor is configured as a pull-down resistor (the default configuration), the combination 
of pull-up and pull-down resistors on this line acts as a voltage divider, holding the line at +2.5V in the 
absence of an external signal.  This configuration is required for single-ended inputs using the ‘+’ lines 
alone; it is desirable for unconnected inputs to prevent the pick-up of spurious noise; it is permissible for 
differential line-driver inputs.