ARMweb Pin Description
 
Rev 4 and 5

32 pins available to the user, 5 of which can be analog inputs, and one dedicated analog input

With Rev 4 the pin numbering for the ARMweb will reflect the assignment native to the LPC2138.  The revision of the board is etched on the backside of the board.

P0(7)
P0(8)
P0(9)
P0(10)
P0(11)**
P0(12)
P0(13)
P0(15)
P0(17)
P0(18)
P0(19)
P0(20)
P0(21)
P0(22)
P0(23)
P0(25)
--
P0(27)
P0(28)
P0(29)
P0(30)
P0(31)++

IO(7)
IO(8)
IO(9)
IO(10)
IO(11)**
IO(12)
IO(13)
IO(15)
IO(17)
IO(18)
IO(19)
IO(20)
IO(21)
IO(22)
IO(23)
IO(25)
--
IO(27)
IO(28)
IO(29)
IO(30)
IO(31)++

TXD(1)
RXD(1)












AD(4), DAout
AD(5)
AD(0)
AD(1)
AD(2)
AD(3)

IO(7) is connected to LED and PUSHBTTON
as an input the push button is 0 when pressed

**IO(11) is open drain when an output (i.e. can not pull up)

IO(15) also controls LED (when low, the LED will be lit)

Input/Outputs  -- user controlled
0-3.3V level, 4mA drive when configured as Outputs

5V tolerant 

- use limiting resistor when connecting to a 5V supply

AD(5) is always an analog input, IO(26) does not exist

10 bit A/D inputs
when used as analog lines,

voltage levels should not exceed 3.3V

++IO(31) is always an output

P1(16)
P1(17)
P1(18)
P1(19)
P1(20)
P1(21)
P1(22)
P1(23)
P1(24)
P1(25)

IO(48)
IO(49)
IO(50)
IO(51)
IO(52)
IO(53)
IO(54)
IO(55)
IO(56)
IO(57)


Input/Outputs  -- user controlled

0-3.3V level, 5 volt tolerant, 4ma drive when outputs


 
Port pins can be controlled with the P0..P4 keywords.  Port 0 pins can be accessed with the original IN, OUT... keywords .  More details on the FIOs can be found in the NXP User Manual.
Dual Use AD pins
 
On reset or power up the AD pins are configured as IO inputs.  To change those to analog IOs, the user must individually read them as AD(x) commands.  After that they will remain analog inputs until the next reset or power up.
 
PWM pins -- not yet implemented
 
All pins can be used for the software PWM function, and <TBD> pins can be used for the hardware driven HWPWM function.
 
Battery Real Time Clock
 
The ARMweb board is designed to accept a Panasonic ML2020/H1C rechargeable Lithium battery at position BT1. This battery powers the real time clock of the LPC2138.  The contents of RAM is not kept alive while running on battery, and the CPU restarts the user program in Flash when power is restored.  This battery is designed to maintain power for a few days without power, and will recharge fully in about 1 day.
 
LED 
 
On the beta units, this is connected to IO(16) not 15. On later units while the LED is connected to IO(7), the silkscreen shows it as connected to IO(15), and the example programs for the ARMmite and ARMexpress use IO(15).  So firmware on the board allows IO(15) to also control the LED.
 
U6 has duplicate connections for IO(17)-IO(20).  U6 is designed to accept a ULN2803.
 
The bottom proto area connects neighboring pairs of pins.  In the top proto area near C23, neighboring triplets of pins are connected horizontally.
 
In addition the ARMweb can be ordered in larger quantities with a switching power supply, which replaces U4, C1 and C9 with U1, D2, L4, C1 and C9
 
Pin spacing
 
The spacing in the prototype area is 0.1" and the terminal strip row on the right side is designed for 3.5mm terminal strips.
 
Rev 2,3

31 pins available to the user, 6 of which can be analog inputs

The revision of the board is etched on the backside of the board.

IO0
IO1
IO2
IO3
IO4
---
IO6
IO7
IO8
IO9
IO10
IO11
IO12
IO13
IO14++

AD0
AD1
AD2
AD3
AD4
AD5













 

Input/Outputs  -- user controlled

0-3.3V level

4mA drive when configured as Outputs

5V tolerant  - use limiting resistor when connecting to a 5V supply

10 bit A/D inputs

when used as analog lines, voltage levels should not exceed 3.3V

++IO14 is always an output

AD5 is always an analog input, IO5 does not exist

IO15



Input/Outputs  -- user controlled

controls LED (when low, the LED will be lit)
as an input also connects to the push button (0 when pressed)
IO16
IO17
IO18**
IO19
IO20
 


Input/Outputs  -- user controlled

0-3.3V level, 5 volt tolerant, 4mA drive when output

**IO18 is open drain when an output (i.e. can not pull up)

BUS0
BUS1
BUS2
BUS3
BUS4
BUS5
BUS6
BUS7
BUS-RW
BUS-CS


 

Input/Outputs  -- user controlled

0-3.3V level, 5 volt tolerant, 4ma drive when outputs

this functions as a byte-wide bus with control of RW and CS