RM310 NXP Semiconductors, RM310 Datasheet - Page 14

• Manufacturer Part Number: RM310
• Description: Ht Rm 310 Hitag Tm Mini Reader Module
• Manufacturer: NXP Semiconductors

02-10-1998
3.
Communication with the host is carried out via an 8 Bit parallel interface with two control lines.
3.1.
3.1.1.
The interface needs in total 10 lines (8 data lines and 2 control lines). The data lines are bi-
directional, while the control lines are unidirectional. The control lines from host to reader module
(host control data /HCDA) and from reader module to host (reader control data /RCDA ) are low
active. By activating the control line either the host or the reader module indicate that data is on
the data line. The respective counter part sets its control line to LOW for a short period of time,
while the rising ramp of the control line indicates that the data transmission has been finished.
Graph: Timing diagram
A bus conflict can never occur, since communication is always initiated by the host. The reader
module responds upon the request command of the host, while the host has to wait for the re-
sponse of the reader module. If the reader module does not respond within the specified time of 1s
for this command (see appendix A: Timing Interface), a time out occurs and the host starts again
with a request.
Since both the host and the reader module can send data, the data lines should only be operated
when also the respective control line indicates data.
8 Bit Data
Interface HT RM310
General Definitions
Hardware
HCDA
RCDA
Host Data
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Rev. 2.3
Host Data
Host
Host Data
ReaderData
Htrm310.doc/HS
ReaderData
HT RM310