Symbol SE 2223, Integration Manual

Page: 89 / 260

8-2
SE 2223/3223 Scan Engine Integration Guide
AC Electrical Characteristics
For the AC electrical characteristics shown in Table 8-1 , Tamb = -30
°
C to 60
°
C, V
BATT
= 4.5
V to 5.5 V. All output lines are measured with 10K pull-up.
Table 8-1. Timing Characteristics
Symbol Figure Parameter Min Max Unit
General Characteristics
t
f
Figure 8-1 High-to-Low fall time, all outputs,
C
L
= 50 pf
1.0 µsec
tr Figure 8-1 Low-to-High rise time, all outputs,
C
L
= 50 pf
1.0 µsec
Serial I/O Timing, Host Transmit
trlcl Figure 8-2 Request to Send low to Clear to Send low 0 25 msec
tclxl Figure 8-2 Clear to Send low to first start bit note 2
txlxl Figure 8-2 Byte to byte delay, (see note 1) 990 msec
Serial I/O Timing, Decoder Transmit, (see Note 3)
tvlvl Figure 8-4 Byte to byte delay, (see note 1) 99 msec
tvhvh Figure 8-3 End of the packet to RTS* high note 4 msec
Notes:
1.If byte to byte delay exceeds the maximum specified time, a transmission error occurs. The
sender must retransmit the entire packet.
2. The host may hold the Host RTS* low indefinitely, but it locks out the SE 2223/3223 from
transmitting.
3. The decoder may transmit any time the Host RTS* is high.
4. The host should release its Host RTS* as soon as possible after transmitting so that the
decoder can process the message.
5. The SE 2223/3223's micro-controller is in full operation whenever the PWRDWN line is driven
low.
6. See Power Management on page 1-5 if trigger is not pulled after the maximum specified
amount of time.
7. In addition, refer to Parameter # 88h on page 9-13 and Parameter # 8Ah on page 9-15.