     
© Radiometrix Ltd
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SpacePort Evaluation Kit can
be used to evaluate the Radiometrix SpacePort, Radio Packet Controller
modules. LED indicators are provided to show system status and
to facilitate range testing and installation site surveys. Internal
EEPROM values can be configured through parallel port connection
to PC using RPC Development Kit Software.
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Figure 1: SP2-433-160 in SpacePort Evaluation Kit |
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Range of Features
- A pair of Evaluation PCBs to evaluate SP2,
RPC and FRPC modules
- Direct interface to Parallel port
- Visual indications of operational mode and
test results through LEDs
- Access to internal diagnostic/Test modes
and EEPROM using RPC Development Kit Software
- All I/O are brought out with adjacent headers
for developing applications and analyzing signals
- PP3 9V Battery operation makes the board
portable for easy wireless evaluation
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Kit
Contents
- 2 SP2-433-160 modules (RPC or FRPC should be ordered separately)
- 2 Evaluation boards
- 2 1/4 wavelength whip antennas (433MHz)
- 2 9V battery (PP3)
- BiM2 data sheet
- 1 SP2 data sheet
- 1 SP2 Evaluation Kit manual
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Optional requirement
- DB25M-DB25F parallel extension/straight
through cable
- PC/laptop with ECP parallel port with MS-DOS,
Win3.X, Win95/98.
- RPC Development Kit Software
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| The following status
LEDs will be activated depending on which mode is selected: |
| LED |
Indication |
| TX (Red) |
Transmitter enabled |
| RX (Green) |
Receiver enabled |
| Power (Green) |
Evaluation Kit is switched on |
| SIGNAL (bright Red) |
Valid preamble detected |
| OK (bright Yellow) |
Valid packet received / Test passed |
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1. Standalone Operation
This mode selects the internal diagnostics
modes built into the RPC, FRPC or SP2.
Set-up:
- Connect the 1/4 wavelength antenna into
the antenna terminal on the evaluation board. Plug the SP2 into
the DIL socket marked SpacePort. RPC/FRPC should be plugged
in with RPC/FRPC IC facing the Evaluation Kit and shielding
can or module facing the other way.
- Connect a 7.5VDC-24VDC supply or 9V battery
to the supply input terminals and slide the power switch to
ON position.
- Put the DEBUG jumper on and press 'Reset'
- The Hex switch selects the required debug
mode 0 to 8. A reset is not required after a mode change.
Digital Storage Oscilloscope probes can
be connected to TXD/AF, TX, RX to monitor data transmission to
and from RF circuit. Probes can be connected to TXR, TXA, RXR,
RXA and D3:D0 data lines to monitor data upload/download from/to
Host/PC.
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| 1.1 Diagnostic Modes |
| Mode |
Name |
Function |
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0
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RX-ON |
Preamble detector ON (SIGNAL
LED lit = valid preamble detected) |
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1
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RX-PULSE |
10ms on: 10ms off, preamble
detector on SIGNAL LED |
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2
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TX-ON-PRE |
Preamble modulation - transmit
continuous preamble |
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3
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TX-ON-SQ |
100Hz square wave modulation,
for TX testing using spectrum analyser, etc. |
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4
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TX-ON-255 |
Random 160kbps data for eye
diagram tests, sync on RXR |
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5
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TX-PULSE |
Preamble bursts (EE 01h setting):
10ms OFF, RX lock in tests |
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6
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ECHO |
Transponder mode, unit re-transmits
any valid packets received |
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7
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RADAR |
Send ASCII test packet "RADIOMETRIX
/ TEST PACKET WITH 60 DATA BYTES / RPC32 V3.0 XX" and
listen for echo. XX is packet number |
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Mode 0 - Preamble Detector
In this mode, receiver circuit is continuously
powered up (RX LED on) and if preamble, 80kHz or 160kbps square
wave signal is detected the SIGNAL line is pulled low lighting
the SIGNAL LED to indicate valid Preamble is detected. RXR will
also be pulled low lighting the OK LED to indicate a pass.
If the RESET jumper is inserted, then the internal Fast Radio
Packet Controller will be disable enabling the internal BiM2 equivalent
receiver circuit to function independently.
Mode 1 - Pulsed Receiver
Receiver is switched on for 10ms and SP2 checks
for preamble. If preamble is detected the SIGNAL line is pulled
low. This will light up the SIGNAL LED. If not, the Receiver is
turned off for 10ms and the process is repeated. OK LED will also
light up to indicate a pass. This mode can be used to test the
power up time and settling time of the receiver circuit.
Mode 2 - Transmit Preamble Modulation
Transmitter is turned on continuously and preamble
(160kbps square wave) is transmitted. This complement mode can
be used with Mode 0 as a pair.
If the RESET jumper is inserted, then the internal Fast Radio
Packet Controller will be disable enabling the internal BiM2 equivalent
transmitter circuit to function independently.
Mode 3 - Transmit 100Hz (200bps) square wave
modulation
Transmitter is turned on continuously and 100Hz
square wave signal is transmitted which can be used to estimate
the FM deviation and power levels of the RF transmitter circuit
using a spectrum analyser.
Mode 4 - Transmit Random Code
Transmitter is turned on and the carrier is
modulated by a 8 bit maximal length (255) pseudo-random code at
6.25ms per bit (at 160kbps). On the receiving end, the data output
AF line can be connected to an Oscilloscope to obtain an eye diagram.
An eye diagram is an oscilloscope display in
which a pseudo-random data signal from AF output of a receiver
is repetitively sampled and applied to the vertical input, while
the data rate (RXR) on the transmitting unit is used to trigger
the horizontal sweep.
System performance information can be derived
by analyzing the display. The horizontal width of the lines gives
the jitter (phase noise) and the rise and fall times of the data
pulses can be measured from the "crossings". An open
eye pattern corresponds to minimal signal distortion. Distortion
of the signal waveform due to intersymbol interference and noise
appears as closure of the eye pattern.
Mode 5 - Pulsed Preamble Transmitter
The transmitter is turned on and normal preamble
(length used for normal data transmission) is sent. Then transmitter
is turned off and waits for 10ms before another cycle. This is
used to measure the lock in time of the receiver.
Mode 6 - Echo/Transponder
Receiver is turned on to checks for preamble
and if a preamble is found, then receiver locks on to the data
and receives the data packet. SIGNAL LED will be turned on if
valid preamble is detected.
Then error check is carried out and if it passes, the OK LED is
turned on. Receiver waits for a Transmit to Receive Change Over
Delay period. Then it retransmits (echoes back) the packet to
the transmitter.
Echo or transponder mode is very useful for
remote loop-back testing of user host software and for "ping-pong"
range testing in conjunction with the other development board
in RADAR mode.
Mode 7 - Radar
Transmitter is turned on and sends a packet
RADIOMETRIX / TEST PACKET WITH 60 DATA BYTES / RPC32 V3.0 XX as
test data where XX will be a Packet Counter. Then transmitter
is turned off and receiver is turned on. Unit on this mode checks
for preamble and if it finds a valid preamble, then it locks on
to the data and receives the packet. Then error check is carried
out and if it passes, the OK LED is turned on.
Even if a valid packet was not received, it
will continue the above process but the packet counter value will
be increased with each transmission.
This mode can be used along with Mode 6 (Echo
Mode) to function as a 'Pin-Pong' system. This provides a very
effective method for Range Testing and Antenna Type Evaluation.
If one eval kit is set to Mode 6, then other eval kit can be set
to Mode 7. By walking around the site where the final product
based on the Radiometrix Modules are going to be used, the range
and antenna type requirements, interference, etc could identified
well in advance. The OK LED will be continuously lit with no flickering
as long as the 'Ping-Pong' the units are within reliable radio
range and the wireless link is error free.
Mode F - Normal RPC Mode
DEBUG jumper should be removed and the RESET
button should be depressed to exit from Debug mode to normal SpacePort
operation. Therefore, Spaceport can be interfaced with Host Microcontroller
or a PC to send/receive data packets.
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 Figure
2: SpacePort Evaluation Kit circuit
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2. Transceiver Operation
If RESET jumper is inserted, the internal Packet
Controller IC will be RESET leaving direct access to raw RF Transceiver.
Jumper across RX-GND will enable receiver circuit and jumper across
TX-GND will enable transmitter circuit.
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3. PC or Laptop Operation
Set-up
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Connect the antenna into the antenna terminal on the development
board and also plug the SP2 into the socket.
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Connect a DC supply/9V battery to the supply input terminals
and switch on.
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Connect the development board to the LPT port of a PC or
Laptop with DB25M-DB25F parallel extension/straight through
cable
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Remove debug jumper.
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Download the RPC Development Kit software files into a suitable
directory on your hard disk.
http://www.radiometrix.co.uk/products/rpceval/rpc_soft.htm
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Software Overview:
The RPC Development Kit software gives
immediate access to a Radiometrix SP2 module and enables simple
ASCII message transmission/reception. The software will display
the EEPROM memory map of the SP2 which can be changed to configure
the SP2 parameters.
For Bidirectional PS/2 or Extended Capabilities
Port (ECP) in new PCs
It contains the following files:
DEMO.BAT Batch file to set the Byte Mode or PS/2 Mode in ECP before
running SP2 software (Run this file)
RPC-BI.EXE main PS/2 SP2 driver program
RPC.DAT ASCII data file holds system information used by SP2-BI.EXE
D.A sample ASCII test files
D.B
D.C
D.D
D.E
The main program RPC-BI.EXE is designed
to run under MS-DOS 3.3 or higher on any IBM PC or compatible
with printer port set to ECP mode.
Using this program it is possible gain
access to the onboard EEPROM to evaluate the extended functionality
provided via the Reserved Memory settings and to also read/write
the User EEPROM area.
The program provides a set of commands
allowing the user to operate the SP2 module. These command functions
enable the user to include send and receive messages, write to
EEPROM memory, send continuous messages to the SP2 and enable
the 7 SP2 debug modes.
Upon start-up of the utility if an SP2
is connected to the parallel port and is working, the Reserved
Memory and User Memory areas of the display will be updated.
The Outgoing and Incoming message area
can be expanded or reduced as the user requires by pressing the
TAB key (or alternatively entering switcH at the command prompt).
This has the effect of either hiding or showing the user memory
area. In order to view the help list properly the display needs
to be in the expanded mode.
Messages sent from the SP2 are displayed under
the Outgoing (TX) message heading to the left of the display.
Messages received by the SP2 are displayed under the Incoming
(RX) heading to the right of the display.
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| Command set:
The following list has been taken from the
RPC demonstration program and details the commands which are available
for evaluating the SP2.
| COMMAND |
DESCRIPTION |
| Reset
[n] |
Reset the SP2; Test mode (n
= 0 - 8) |
| reaD
address |
Read from memory
address (Addr = 00 - 3F) |
| Send
[$] string |
Transmit string via SP2; $
selects preamble |
| Write
address data |
Write data to SP2 memory address
(00 - 3F) |
| Clear |
Clear the display
output window |
| switcH
or <TAB> |
toggle memory display window
On/Off |
| File [delay] file
[file...] |
Send a file(s)
to the SP2 |
| |
delay = delay between files
(0.25s increments) |
| Test |
execute the file send test
list |
| stoP
or <^X> |
to stop repeating file send
(Test & File) |
| Help |
Display this help information |
| eXit
or <F3> |
Exit from this demo program |
| <ESC> |
Erase current command line |
| <TAB> |
Switch display between memory
and output |
Note:
1. The capital letter in each command may be used in place of
the full word.
2. All values required by specific commands should be entered
in hex.
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| Commands in Detail: |
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Note: Square brackets [] means
the argument(s) are optional.
Angle brackets <> means the argument(s) are required.
The capital letter in the command represents an abbreviation of
that command.
| Reset [0-8] |
send a RESET
to the RPC. |
|
sets the RPC
into the specified demo mode. |
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example: >R
reset RPC |
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>R7
reset SP2 into debug mode 7 (RADAR) |
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| reaD <address> |
read the EEPROM
memory at location <address> |
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the address should
be in the range of 0x00 - 0x3F |
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e.g.: >read
20 |
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| Send [$] <string> |
Transmit the
given string via the SP2 |
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Preceding the
string with a $ sign will enable extended preamble to be used
when transmitting the packet. If more than 27 bytes of data
are entered on the command line, the string will be broken
into 2 SP2 packets and transmitted. |
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example: >S
THIS IS A TEST send 'THIS IS A TEST' |
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>S$Is
any body out there ? ; extended preamble |
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| Write <addr>
<data> |
Write data to
the specified SP2 EEPROM location. |
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The allowable
memory range is from 0x00 to 0x3F. Data represents a single
byte between 0x00 - 0xFF. |
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example: >W
00 4 writes 04h into SWITCHES (00h) |
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>W
08 80 will set PS1 on reset |
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| eXit or <F3> |
Typing either
EXIT or X, or pressing F3 will exit from the demonstration
program back to the command prompt. |
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| Clear |
Clear the display
output window. |
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| stoP or <^X> |
Stop the repeating
file send (Test & File commands). |
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| Help |
Display this
help information as shown in section SP2DEMO commands. |
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| <TAB> |
Switches the
display between the memory display and the expanded output
display. |
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| <ESC> |
Clear the current
command line |
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| File [delay]
file [file...] |
Send a file to
the SP2. A maximum of 3 files can be givenon the command line.
The file names should contain only alpha characters (e.g.
fred1.txt <- not allowed. freda.txt <- allowed). The
[dly] enables a delay of between 0x00 and 0xFF seconds between
files being sent. Using the delay will enable the files to
be repeated continuously using the delay value between them.
Without the delay value the file(s) will only be sent once. |
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This is NOT a
file transfer function. i.e.; it will not copy the file to
the destination. |
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If any lines
in the file contain more than 27 bytes, the line will be broken
into multiple blocks of 27 bytes. They will NOT be reassembled
into full lines by the receiver. |
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e.g. file 2 autoexec.bat
config.sys |
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example: >F
SP2.DOC transmits this file |
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| Test |
Execute the test
file command line from the SP2.DAT file |
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See SP2 Configuration
File details later for a description of SP2.DAT command line
used with this command. |
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example: >T
repetitively sends the test files. |
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SP2 Configuration File:
The demonstration program requires a configuration file. This
file is called SP2.DAT. Following is an example SP2.DAT file:
PORT = 378
COLOUR = 1
FILE = 8 d.a d.b d.c d.d d.e
PORT = <xxx>
This entry determines the base address of the PC printer port.
The value is entered as a hex value.
COLOUR = <0 | 1>
This is a Boolean of either 0 or 1.
Setting this entry to 0 disables the colour display. i.e.; all
output will be in black and white. This is suitable for a monochrome
display device such as a laptop.
Setting this entry to 1 will enable the coloured output.
FILE = <delay> <file1> <file2> <file3>
This entry has the same format as the FILE command.
It is the command line used when the TEST command is entered.
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Appendix A: Using a printer port
to drive the SP2
For New PCs: Bi-directional Port (PS/2)
Port requirement: 8 bit bi-directional PS/2 (PS/2 or ECP
set to PS/2 Mode / Byte Mode)
In PS/2 Mode, Status Lines are used for Control line input from
SP2 (RXR, TXA) and Printer Port Control Lines are used to output
the SP2 Control signals (RXA & TXR). In Bidirectional PS/2
mode, Printer port data lines can be used as SP2 data lines in
bidirectional mode.
Most of the PCs come with Extended Capabilities Port (ECP). ECP
can be set to operate in PS/2 compatible bidirectional mode. Program
supplied with bidirectional version will automatically change
the mode from ECP to PS/2 and change it back to ECP when the SP2
Dev Kit software is closed.
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PC Printer port registers
(addresses given for base address of 0378h)
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| 0378 |
data register
|
b7 |
b6 |
b5 |
b4 |
b3 |
b2 |
b1 |
b0 |
| |
|
- |
- |
- |
- |
- |
RES |
RXR |
TXA |
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| 0379 |
status register
|
b7 |
b6 |
b5 |
b4 |
b3 |
b2 |
b1 |
b0 |
| |
|
- |
Int |
TXA |
RXR |
- |
- |
- |
- |
| |
| 037A |
control register
|
b7 |
b6 |
b5 |
b4 |
b3 |
b2 |
b1 |
b0 |
| |
|
- |
- |
dir |
Ien |
D3 |
D2 |
D1 |
D0 |
| For Extended
Capabilities Port (ECP) only |
| 077A |
Extended Control |
b7 |
b6 |
b5 |
b4 |
b3 |
b2 |
b1 |
b0 |
| |
Register (ECR) |
0 |
0 |
1 |
- |
- |
- |
- |
- |
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Printer Port can be configured to operate in ECP mode by changing
the Printer Port setting in BIOS from SPP or EPP to ECP. BIOS
setup can be accessed by pressing DEL key for AWARD BIOS or F1
for AMI BIOS when booting the computer. Parallel Port settings
can be changed in the Integrated Peripherals section of the BIOS
setup.
However, it may be necessary to change it back to SPP or EPP
mode for some printers to operate properly.
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| int |
+ve transition interrupt bit, see "interrupt
drive" |
| Ien |
bit is internal interrupt enable, not
used if polling used |
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1 = interrupt enable , 0 = disabled (polled
operation) |
Note: RXA and TXR pins are inverted
drives from the register ie a 1 in the control register gives
a 0 on the pin all other registers / bits are true.
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| |
| Appendix
B: Sample SP2 Driver subroutines for a PIC Host |
Figure
3: SpacePort Evaluation Kit interfaced to a PIC16F870 host
microcontroller
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SP2 Evaluation Kit can be interfaced to a Host PIC microcontroller
as shown above. PIC16F870 has PortB with 8 I/O pins which can
be assigned to communicate with SP2 Eval Kit. UART in PortC can
be interfaced to a Serial COM Port via an RS232 driver.
The following subroutines may by used by a PIC16F870 host microcontroller
to upload serial data it received from its serial port to SP2
and download the data packet from SP2 and send it out via its
serial port to a PC.
OUT_BYTE & IN_BYTE
Additionally LISTEN_BUS is called on completion of a packet transfer
to the SP2 to return the data bus to high impedance input mode
(default state).
|
| TITLE
'SP2 DRIVERS FOR A PIC' |
| |
|
list |
p=16F870 |
r=hex |
| ; |
| ;STANDARD
EQUATES - dedicated data file locations PAGE 0 |
| INDF |
EQU
|
0 |
;
INDIRECT CALL , OPCODE WILL USE |
|
|
|
; FSR (04h) AS
FILE POINTER |
| TMR |
EQU
|
1 |
;
8 bit timer |
| PCL |
EQU
|
2 |
;
low order program counter |
| STATUS |
EQU
|
3 |
;
STATUS BITS |
| IRP |
EQU
|
7 |
;
Not used on 16c84, |
|
|
|
; indirect addressing
page bit |
| RP1 |
EQU
|
6 |
;
Not used on 16c84 , high order |
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; file addressing
page bit |
| RP0
|
EQU
|
5 |
;
file page, 0=PAGE 0 , 1=PAGE 1 |
|
|
|
; e.g. DDR's etc. |
| TO |
EQU
|
4 |
;
cleared on watchdog time-out |
| PD |
EQU
|
3 |
;
cleared on sleep instruction |
| Z |
EQU
|
2 |
;
ZERO flag |
| DC |
EQU
|
1 |
;
DIGIT CARRY flag (4th bit) |
| C |
EQU
|
0 |
;
CARRY flag |
| ; |
|
|
|
| FSR |
EQU
|
4 |
;
file pointer |
|
|
|
; (indirect file
address register) |
| ; |
|
|
|
| PORTA |
EQU
|
5 |
;
i/o port A - 5 Bits , Free for |
|
|
|
; applications
program use. |
| ; |
|
|
|
| SP2 |
EQU
|
06 |
;
USE PORT B ON PIC |
| ;
Bit assignments for SP2 PORT |
| D7 |
EQU
|
7 |
;
Bi-Dir data , D3 |
| D6 |
EQU
|
6 |
;
Bi-Dir data , D2 |
| D5 |
EQU
|
5 |
;
Bi-Dir data , D1 |
| D4 |
EQU
|
4 |
;
Bi-Dir data , D0 |
| TXA |
EQU
|
3 |
;
INPUT , active low TX accept from SP2 |
| TXR |
EQU
|
2 |
;
OUTPUT , active low TX request to SP2 |
| RXA |
EQU
|
1 |
;
OUTPUT , active low RX accept to SP2 |
| RXR |
EQU
|
0 |
;
INPUT , active low RX request fromSP2 |
|
|
|
; (interrupt if
required) |
| ; |
|
|
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| PCLATH |
EQU |
0A |
; Holding reg
for program counter |
|
|
|
; high byte |
| INTCON |
EQU |
0B |
;GIE,EEIE,TOIE,INTE,RBIE,TOIF,INTF,
|
|
|
|
; RBIF interrupts. |
| ;
STANDARD EQUATES - dedicated data file locations - PAGE 1 |
| OPTION |
EQU |
81 |
; RBPU,INTEDG,RTS,RTE,PSA,PS2,PS1,PS0 |
| DDRA |
EQU |
85 |
; I/O direction
reg ,portA 1= i/p 0= o/p |
| SP2_DDR |
EQU |
86 |
; Data direction
register for port B (SP2) |
|
|
|
; This register
is in BANK 1 of the register file. |
| ;-------------------------------------------------------------------- |
| ORG 0 |
|
|
|
| ONRESET |
GOTO |
START |
; jump to main
program |
| ; |
|
|
|
| ;
Initialise PORT B to drive SP2. |
| START |
BSF |
STATUS,RP0 |
; select page
1 |
|
MOVLW |
B'11111001' |
; TXR & RXA
O/P , Rest as inputs |
|
MOVWF |
SP2_DDR |
|
|
BCF |
STATUS,RP0 |
; select page
0 |
| ; |
|
|
|
| ;
SUBROUTINE - IN_BYTE |
| ; |
IN_BYTE
- READ A BYTE FROM THE SP2 INTO FILE POINTED |
| ; |
|
TO
BY FSR W IS DESTROYED |
| ; |
|
|
|
| ; |
NOTE |
THIS
ROUTINE WILL HANG THE HOST UNTIL THE HOST |
|
|
COMPLETES
THE TRANSFER OF TWO NIBBLES |
|
|
|
|
| ; |
|
THIS
SUBROUTINE CAN BE CONFIGURES TO RUN |
| ; |
|
AS
PART OF AN INTERUPT HANDLER IF THE RXR |
| ; |
|
LINE
FROM THE SP2 IS USED TO TRIGGER A HOST INTERUPT |
| ; |
|
|
|
| IN_BYTE |
BTFSC |
SP2,RXR |
; WE GOT A RX
REQUEST YET ? |
|
GOTO |
IN_BYTE |
; NO , SO LOOP
BACK AND WAIT |
|
|
|
|
| ;
READ THE LS NIBBLE FROM THE SP2 |
|
BCF |
SP2,RXA |
; ACCEPT THE REQUEST
(SET ACCEPT LOW) |
| ; |
|
|
|
| AWAITDATA |
BTFSS |
SP2,RXR |
; HAS REQUEST
GONE UP ? i.e. data is present |
|
GOTO |
AWAITDATA |
; LOOP BACK TILL
IT DOES |
| ; |
|
|
|
|
NOP |
|
; TIME DELAY TO
ENSURE DATA STABLE |
|
|
|
; BEFOR READ |
|
MOVF |
SP2,W |
; READ THE LS
NIBBLE FROM THE BUS |
|
BSF |
SP2,RXA |
; TELL SP2 WE
GOT NIBBLE (ACCEPT = 1) |
|
ANDLW |
B'11110000' |
; JUST THE DATA |
|
MOVWF |
INDF |
; SAVE LS NIBBLE
IN TARGET FILE (VIA FSR) |
|
SWAPF |
INDF,F |
; RIGHT JUSTIFY
LS NIBBLE |
| ; |
|
|
|
| ;
NOW GET MS NIBBLE FROM THE SP2 |
| INNIBBLE |
BTFSC |
SP2,RXR |
; WE GOT NEXT
RX REQUEST YET ? |
|
GOTO |
INNIBBLE |
; NO , SO LOOP
BACK AND WAIT |
| ; |
|
|
|
|
BCF |
SP2,RXA |
; ACCEPT REQUEST
(SET ACCEPT LOW) |
| ; |
|
|
|
| AWAITD1 |
BTFSS |
SP2,RXR |
; HAS REQUEST
GONE UP ? i.e. data is present |
|
GOTO |
AWAITD1 |
; LOOP BACK TILL
IT DOES |
| ; |
|
|
|
|
NOP |
|
; TIME DELAY TO
ENSURE DATA STABLE |
|
|
|
; BEFOR READ |
|
MOVF |
SP2,W |
; READ THE MS
NIBBLE FROM THE BUS |
|
BSF |
SP2,RXA |
; TELL SP2 WE
GOT NIBBLE (ACCEPT = 1) |
|
ANDLW |
B'11110000' |
; JUST THE DATA |
|
IORWF |
INDF,F |
; COMBINE MS NIBBLE
WITH LS NIBBLE |
|
|
|
; ALREADY IN THE
FILE (VIA FSR) |
|
RETURN |
|
|
| ;
A BYTE HAS BEEN READ FROM THE SP2 INTO ADDRESS POINTED AT
BY FSR |
| ;-------------------------------------------------------------------- |
| ;
SUBROUTINE- OUT_BYTE |
| ; |
OUT_BYTE-
WRITE A BYTE FROM FILE POINTED TO BY FSR TO SP2 |
| ; |
|
W
IS DESTROYED |
| ; |
|
|
|
| ; |
NOTE |
THIS
ROUTINE WILL HANG THE HOST UNTIL THE SP2 |
|
|
ACCEPTS
THE TRANSFER OF TWO NIBBLES |
| ; |
|
|
|
| ; |
WARNING
- OUT_BYTE WILL SET THE DATA BUS TO DRIVE |
| ; |
|
AFTER
DETECTING |
| ; |
|
A
TXA FROM THE SP2. |
| ; |
|
THE
CALLING ROUTINE MUST SET 4 DATA LINES |
| ; |
|
BACK TO I/P |
|
| ; |
|
ON
COMPLETION OF PACKET TRANSFER |
| ; |
|
(i.e.
call LISTENBUS) |
| ; |
|
|
|
| OUT_BYTE |
SWAPF |
INDF,W |
; GET LS NIBBLE
FROM FILE (VIA FSR) INTO |
|
|
|
; BITS 4 to 7
of W |
|
ANDLW |
B'11110000' |
; JUST THE NIBBLE |
|
IORLW |
B'00000010' |
; SET TXR LOW,
LEAVE RXA HIGH |
|
MOVWF |
SP2 |
; SET TXR LOW
, OUTPUT NIBBLE |
| ; |
|
|
|
| WACCEPT |
BTFSC |
SP2,TXA |
; WE GOT A TX
ACCEPT BACK YET ? |
|
GOTO |
WACCEPT |
; NO , SO LOOP
BACK AND WAIT |
| ; |
|
|
|
| ;
WE GOT ACCEPTANCE SO IT'S OK TO DRIVE BUS |
|
BSF |
STATUS,RP0 |
; SELECT PAGE
1 |
|
MOVLW |
B'00001001' |
; DRIVE BUS |
|
MOVWF |
SP2_DDR |
|
|
BCF |
STATUS,RP0 |
; SELECT PAGE
0 BUS IS NOW DRIVING |
| ; |
|
|
|
|
BSF |
SP2,TXR |
; REMOVE REQUEST,
DATA IS ON BUS |
| WDUN |
BTFSS |
SP2,TXA |
; HAS DATA BEEN
READ? |
|
GOTO |
WDUN |
; WAIT TILL SP2
REMOVES ACCEPT |
| ; |
|
|
|
| ; |
LS
NIBBLE OF (FSR) IS SENT , NOW DO MS NIBBLE |
|
MOVF |
INDF,W |
; GET MS NIBBLE
FROM FILE (VIA FSR) |
|
ANDLW |
B'11110000' |
; JUST THE MS
NIBBLE |
|
IORLW |
B'00000010' |
; SET TXR LOW
(BIT 2), RXA STAYS HIGH |
|
MOVWF |
SP2 |
; OUTPUT NIBBLE
+ TXR LOW WACCEPT1 |
| WACCEPT1 |
BTFSC |
SP2,TXA |
; WE GOT A TX
ACCEPT BACK YET ? |
|
GOTO |
WACCEPT1 |
; NO , SO LOOP
BACK AND WAIT |
|
BSF |
SP2,TXR |
; REMOVE REQUEST,
DATA IS ON BUS |
| WDUN1 |
BTFSS |
SP2,TXA |
; HAS DATA BEEN
READ? |
|
GOTO |
WDUN1 |
; WAIT TILL SP2
REMOVES ACCEPT |
| ; |
|
|
|
|
RETURN |
|
; BYTE IS SENT
TO SP2 |
| ;-------------------------------------------------------------------- |
| ;
SUBROUTINE - LISTEN_BUS , SET DATA BUS TO INPUT |
| ; |
|
|
|
| LISTEN_BUS |
BSF |
STATUS,RP0 |
; SELECT PAGE
1 |
|
MOVLW |
B'11111001' |
; BUS TO INPUT |
|
MOVWF |
SP2_DDR |
|
|
BCF |
STATUS,RP0 |
; SELECT PAGE
0 |
|
RETURN |
|
|
| ;
BUS IS LISTENING TO SP2 |
|
END |
|
|
|
|
|
Limitation of liability
The information furnished by Radiometrix Ltd is believed to be
accurate and reliable. Radiometrix Ltd reserves the right to make
changes or improvements in the design, specification or manufacture
of its subassembly products without notice. Radiometrix Ltd does
not assume any liability arising from the application or use of
any product or circuit described herein, nor for any infringements
of patents or other rights of third parties which may result from
the use of its products. This data sheet neither states nor implies
warranty of any kind, including fitness for any particular application.
These radio devices may be subject to radio interference and may
not function as intended if interference is present. We do NOT
recommend their use for life critical applications.
The Intrastat commodity code for all our modules is: 8542 6000.
R&TTE Directive
After 7 April 2001 the manufacturer can only place finished product
on the market under the provisions of the R&TTE Directive.
Equipment within the scope of the R&TTE Directive may demonstrate
compliance to the essential requirements specified in Article
3 of the Directive, as appropriate to the particular equipment.
Further details are available on The Office of Communications
(Ofcom) web site:
Licensing
policy manual
|
|
|
