Compatibility with AMW004-A01 (Hornet) AMW006-A1x Datasheet
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©2015 ACKme Networks. http://ack.me July 8, 2015
3 Compatibility with AMW004-A01 (Hornet)
The AMW006-A1x (Hopper) module adapter is pin-for-pin compatible with the existing ACKme AMW004-A01
(Hornet) module adapter with the exception of the UART RTS/CTS connections. A full description of RTS/CTS
compatibility is described in this section.
3.1 Serial Communications Primer
In traditional RS-232 serial UART communication, there are two ends of a communication link. One end is the
Digital Terminating Equipment (DTE = Computer terminal) and the other end is the Digital Communications
Equipment (DCE = modem).
The serial link between these two pieces of equipment can be configured to use hardware flow control signals to
control data flow on the link. Hardware flow control is used by the equipment on each end of the link to signal
when data is ready to be sent, and when the equipment is ready to receive more data. There are typically two
hardware flow control signals known as RTS (Ready to Send) and CTS (Clear to Send).
The RTS (Ready-to-Send) signal is an output from the DCE (modem) and the CTS (Clear to Send) is an output from
the DTE (computer terminal).
3.2 Hopper RTS/CTS Compatibility
The UART flow control signals on the original ACKme AMW004-A01 Hornet module adapter match the traditional
RTS/CTS hardware flow control implementation described in Section 3.1 above. Since a module adapter is
effectively a modem, the Hornet RTS signal is an output, and the Hornet CTS signal is an input.
Unfortunately, designers of the de-facto standard 2mm pitch 2x10 pin sockets commonly used in wireless
embedded applications swapped the definition of RTS and CTS. As a result, the Hornet module adapter does not
work out-of-the-box with baseboards designed for the de-facto embedded wireless standard if UART hardware
flow control is enabled.
Hopper on the other hand, is configured with RTS/CTS signals that match the de-facto standard. There are two
ways to enable backwards compatibility with the AMW004-A01 Hornet:
1. Swap the RTS/CTS signals on your host microcontroller, assuming the host MCU offers this feature.
2. Two zero ohm links, R13 and R14, on the underside of the Hopper PCB can be modified. After the
modification, the operation of the Hopper and Hornet UART with hardware flow control is identical. A
diagram showing how to make the modification is shown below.
configuration is shown on the
Hopper board, and as
horizontal orientation,
black/gray in the detail
diagram.
The Hornet compatible
configuration is shown as red
with vertical orientation,
default
Not Recommended for New Designs