HT-CM400 NXP Semiconductors, HT-CM400 Datasheet - Page 53

• Manufacturer Part Number: HT-CM400
• Description: Ht Cm400; Ht Rm440 Family; Ht Rm800 Family Interface Protocol Reader - Host
• Manufacturer: NXP Semiconductors

98-02-10
3.7.37 SetProxTrmTime
This Proximity Reader command writes new RF-bit-times t_0, t_1, t_p into the EEPROM of the
read/write device.
ATTENTION: It is not necesarry to use this command when working with Philips
Semiconductors Proximity Readers because EEPROM is already initialized to following standard
values:
ATTENTION: The values for t_0, t_1, t_p do not represent the RF-bit-times in s. They have to
be computed. If you provide T0, T1, TP in s you can compute t_0, t_1 and t_p using following
code sequence:
C-Function: void proloc_SetProxTrmTime (BYTE_T t_0, BYTE_T t_1, BYTE_T t_p);
Header-File: PROLIB6.H
Serial protocol:
HOST - READ/WRITE DEVICE
READ/WRITE DEVICE - HOST
Status:
0x05
0x02
t_0 = 0xA9
t_1 = 0x81
t_p = 0xEC
/* TP >= 43 µs; T0 >= T_P + 40 µs; T1 >= T_P + 40 µs; */
t_0=(unsigned char)(32768-((T0-T_P-24)/1.2));
t_1=(unsigned char)(32768-((T1-T_P-24)/1.2));
t_p=(unsigned char)(32768-((TP-24)/1.2));
0xA1
Status
-1 ...
0 ... no error
t_0
(176 s)
(224 s)
(48 s)
SERIAL ERROR
BCC
t_1
Duration of a ‘0’-bit including t_p
Duration of a ‘1’-bit including t_p
Duration of a Modulation Gap
t_p
Page 53 (104)
Rev. 1.0
BCC
Communication Reader-Host
Htswp.doc/HS