Navman 20 GPS Receiver User Manual


 
LA000577C © 2006 Navman New Zealand. All rights reserved. Proprietary information and specications subject to change without notice.
21
Bit Pad function Pin
(LSB) 0 GPIO15/Fwd-Rev 27
1 GPIO1/Wheel Tick 28
2 GPIO3/Gyro In 8
3 GPIO5/SDI 25
4 GPIO6/SDO 24
5 GPIO7/SCLK 26
6 GPIO9/1PPS 29
(MSB) 7 GPIO10/GPS Fix 23
Table 3-3: Pin conguration of the GPIO lines
On the Jupiter 20 D, there is no control of GPIO15, GPIO1, GPIO3, GPIO5, GPIO6 or GPIO7,
and all references to these pins are ignored.
In each of the messages described in the following sections, x represents a hexadecimal digit.
3.5.1 Congure port directions
$PSRF225,xx,xx[*CS] <CR> <LF>
Sets the direction of the GPIO pins. The rst octet is the mask (which ports to override), the
second the new direction. A zero represents an input, and a one an output. This command
must be sent before attempting to manipulate or read any the specied GPIO. It also has the
effect of suspending the normal port functions on the pins specied. Normal operation will
resume following a hardware reset (including any use of the reset line in Push-to-Fix mode).
Response:
$PTTK,GPIO,DIR,xx,xx*CS
3.5.2 Set outputs
$PSRF226,xx[*CS] <CR> <LF>
Changes the specied outputs to high. Other outputs are not affected. There are no
changes to any pins that are congured as inputs.
Response:
$PTTK,GPIO,SET,xx*CS
3.5.3 Clear outputs
$PSRF227,xx[*CS] <CR> <LF>
Changes the specied outputs to low. Other outputs are not affected. There are no changes
to any pins that are congured as inputs.
Response:
$PTTK,GPIO,CLEAR,xx*CS
3.5.4 Read inputs
$PSRF228[*CS] <CR> <LF>
Returns the values on the input pins. Pins congured as outputs read as zero.
Response:
$PTTK,GPIO,READ,xx*CS
This message is sometimes output automatically.
3.6 GPS x output
The GPS x output is an active low output on pin 23 of the module. Whenever the unit has
either a 2D or a 3D x, this output will be low. When the unit has no x, the output will be high.
This function can be overridden and the pin used as GPIO10 using the commands described in
Section 3.5. The GPS x output function returns after a reset.