![background image](http://html1.mh-extra.com/html/rabbit/em1500/em1500_product-manual_3112140046.webp)
42
EM1500 Configuration
5.1.4 Serial Tab (for SER1 - SER4)
Each serial port is configured independently. The tabs along the top select one of the five serial ports,
while the seven tabs lined up vertically under the Network tab correspond to the different parts of the serial
port configuration.
Figure 5.5 Serial Tab of Stand-Alone Configuration Program
Except for flow control, the parameters shown on this screen apply equally to all of the serial ports.
Speed (BPS)
This is the serial port speed in bits per second. Choose from the drop-down menu with
choices ranging from 300 bps to 230400 bps. You may also enter any value between
75 and 230400 in this field. The number should match the data transfer speed of the
attached serial device.
The EM1500 serial ports may all be configured for a wide range of bit rates, including
non-standard speeds. The actual rates which are obtainable must be equal to the base
clock divided by an integer between 6 and 256 inclusive. The base clock is
1,382,400 Hz, giving a range of speeds from 5400 to 230400 bps. Speeds slower than
5400 bps may also be achieved: in this case, the base clock becomes 19200 Hz, which
may be divided by an integer between 4 and 256 inclusive. Thus the slow range of
speeds varies between 75 and 4800 bps.
Because of the requirement for an integer clock divider, the speed resolution is worst
at the highest speeds in each range. For example, the next speed below 230400 bps is
197486 bps (using a divisor of 7 instead of 6). The next speed below 4800 bps is 3840
bps (using divisor of 5 instead of 4).
In practice, all of the most common serial port bit rates are achieved exactly (within
the limit of the crystal oscillator accuracy, which is about 100ppm). Many of the less
common rates, such as 14400 bps, are also exact.
SER3 and SER4 have an upper limit of 115200 bps.
Summary of Contents for EM1500
Page 14: ...10 www rabbit com Introduction...
Page 22: ...18 www rabbit com Getting Started...
Page 76: ...72 www rabbit com EM1500 Configuration...
Page 90: ...86 www rabbit com EM1500 Specifications...
Page 104: ...100 www rabbit com Serial and TCP Protocols...
Page 118: ...114 www rabbit com EM1500 FAQ...