User's Guide

ATOP3.5G Product Description
80447ST10636A rev.10 – 2015-03-03
Reproduction forbidden without written authorization from Telit Communications S.p.A. - All Rights
Reserved. Page 17 of 66
Mod. 0808 2011-07 Rev.2
7.2.2 Internal pins list
Table 3 lists a number of internal pins controlled by the Utility Processor that are of interest to
ATOP 3.5G application programmers. Most of these pins are controlled by low-level software
drivers provided by TELIT and so should not be controlled directly. They are there described only
for reference.
Table 3 Internal microcontroller pins, controlled by TELIT-provided libraries
All these pins are controlled via TELIT-provided libraries and should not be used/controlled directly in any
way.
Pin name GPIO number Description
BB_RESETN P1.25 0 = reset application processor, otherwise should be left floating
BB_POK P1.28 0 = enable application processor
BB_SSI[3:0] P1.20 serial communication channel
P1.21
P1.23
P1.24
BB_SDB[4:0] P2.0 internal communication channel
P2.1
P2.7
P2.8
P3.26
ANT_SW P3.25 antenna switch
BB_UART_RX P4.28 BB UART internally connected to MC UART3 by means of level
shifter
BB_UART_TX P4.29
INT_TEMP P1.31 ADC input to internal temperature sensor. A TELIT-provided
function call converts value to °C. For more information see
section 12.1.
I2C_SDA P0.19 [1] I
2
C bus to SmartMX security processor bridge
I2C_SCL P0.20 [1]
I2C_GATE P2.1 [1] SmartMX security processor bridge control line. This is used to
switch the SmartMX data communication channel between the
base band and the Utility Processor (see Figure 3). This is shared
with one of the BB_SDB pins. For detailed usage instructions, see
Ref 12.
SMX_NRESET P1.26 [1] SmartMX security processor reset line
RFU P1.27 32KHz tree distribution
[1] Only for OM1230/1X0 and OM12030/2X0, with X as defined in Section 5. On all other ATOP 3.5G
variants this pin is RFU.