ARF169 Radio Modems - User guide version V1.4
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Note4
: the default choice of manual exiting from the mode is suitable for use during development, when the user needs to maintain control
over the exit from the command mode.
Programming of a timeout is recommended for use in operation, to enable an automatic return by the modem into the communication mode if
a character chain in the data flow is accidentally assimilated to a request for entry into the command mode.
Note5
: registers S217 and S218 are used to synchronise transmission start:
• either a timeout (S217)
• or a quantity of data in the buffer memory (S218)
The first of these two limits reached triggers transmission start.
When the number of octets in the buffer memory reaches the threshold of register S218 before the timeout of register S217, it is triggering on
data.
On the other hand, when the timeout of register S217 expires before the data in the buffer memory reach the threshold of register S218, it is
triggering on time.
It should be noted that programming register S217 to 0 (no timeout) means that the S218 register threshold must be reached to start transmis-
sion.
Below example of S217 & S218 register usage :
TX RF via S218
S217 = 10 millisecondes
S218 = 3 octets
Condition 3 octets remplie = émission
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15 16 17
Millisecondes
TX RF via S217
S217 = 10 millisecondes
S218 = 3 octets
Condition 10 millisecondes sans nouvel
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15 16 17
octet remplie = émission
Millisecondes
TX RF via S218
S217 = 10 millisecondes
S218 = 3 octets
Condition 3 octets remplie avant
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15 16 17
échéance timeout 10 millisecondes = émission
Millisecondes
6. Document history
Version
Contents
V1.4
Register S243
V1.3
Duty cycle value modification
V1.2
Repeater mode, S217 register value modifed
V1.1
RS485 modification
V1.0
Document created
