Navman LA000508 GPS Receiver User Manual


 
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LA000507G © 2006 Navman New Zealand. All rights reserved. Proprietary information and specications subject to change without notice.
4.2 Data input output specications
All communications between the Jupiter 20 receiver and external devices are through the I/O
surface mount pads. These provide the contacts for power, ground, serial I/O and control. Power
requirements are discussed in Section 4.1.
4.2.1 Voltage levels
The I/O connector voltage levels measured at PWR_IN = 3 V are shown in Table 4‑3.
Signal Parameter Value
TXD & RXD
GPIOs
SPI bus
V
IH
(min) 2.0 V
V
IH
(max) PWR_IN +0.1 V
V
IL
(min) 0.1 V
V
IL
(max) 0.8 V
V
OH
(min) at I
OH
2 mA
2.0 V
V
OH
(max) PWR_IN
V
OL
(min) 0
V
OL
(max) at I
OL
–2 mA
1.0 V
Reset input*
max capacitance Cmax 100 pF
input current max –600 μA
pulse time min 200 μs
*Reset input should not be driven high by external circuits. It
is recommended that this input is driven low by an open drain
interface.
Table 4-3: Interface voltage levels
4.2.2 I/O surface mount pads
Details of the surface mount pad functions are shown in Table 4‑4 and 4‑5.
Pad
No.
Name Type Description
8* GYRO_IN I gyro input (analogue 0–5 V)
27* FWD/REV I fwd/rev input (low=forward, high=reverse)
28* WHEEL_TICKS I wheel tick input
* See also Table 4‑5 for J20/J20S pad functions
Table 4-4: J20D receiver pad functions