Model 152 Smart Card Reader/Writer Operation Instructions
8182760 Revision G Copyright Axiohm 1998 All Rights Reserved
Page 1.1
Chapter 3:
Basic Operation
Transmission Parameters
Each character is transmitted using 8 data bits, no parity, and 1 stop bit.
The factory default speed is 9600 bps. Other speeds may be chosen using the configuration
program. The other speeds are: 38400, 19200, 4800, 2400, and 1200 bps.
Host Protocols
The Model 152 supports three communications protocols to talk with the host. They are: USI2,
TLP-224, TLP-224Turbo
USI2 is a proprietary protocol developed by Axiohm - American Magnetics which has features
allowing it to be used for multi-dropping and for large (up to 64K bytes) messages. Though the
Model 152 does not support multi-dropping at this time, a future variation of the device may.
TLP-224 is a protocol used by several manufacturers of Smart Card devices. There are a core
set of functions defined, which, if used exclusively, provide for plug compatibility between
different manufacturer’s readers. The AMC implementation has all of the core functions plus a
few more which you may use at your discretion.
TLP-224Turbo is an AMC originated variant of the TLP-224 protocol. The standard TLP-224
protocol requires each byte to be split into two ASCII readable bytes for transmission. This
effectively doubles the communication time for each message. The TLP-224Turbo protocol
corrects this problem by simply not splitting bytes. If you like TLP-224, but don’t like its speed,
you may want to try TLP-224Turbo.
Power Cycle/Reset
Cycling the power to the Model 152 will cause the device to loose the contents of volatile
memory, including the information on the current card and selected connector.
When power is restored the device checks the validity of the EEPROM to make sure they are
functioning correctly. The host needs to set all the parameters stored in volatile memory before
resuming.
