ST2203U

Preliminary Ver 2.0

Page 4/5

2006/11/28

Project Name:

DATE:

ITEM

CHECK

NOTE

1

Check the desired frequency matched the VDD

2

Check and use the updated version of data sheet

3

After power on, enter wait-1 mode for 1.5 second before normal operation

4

Initialize user RAM and every related control register

5

Confirm contrast level, duty, frame rate, alternating rate and the display quality of

LCD

6

Before entering power down mode, turn off unused peripheral such as LCD

controller, and LVD

7

Confirm I/O direction, default state, and function enable bits. Enable pull-up for

unused input pins

8

Read from an input port after the signals are stable. Ex. when doing key scan,

delay 12 us from a new scan value then read the return lines.

9

If an input connects to VDD or GND directly, make sure to remove any DC current

from internal pull-up/down resistor after the status is being read.

10

Do not use “ read-modify-write” instructions, e.g. ROR and SMB0, to the registers

that are read-only, write-only or have different functions for read and write. The

registers at least include PA ~ PD, PL, PCD, PFC, PFD, TIEN, PCL, TxCH, TxCL, PRS,

BTREQ, BTCKS, RTCR, RTC, IRRH, PRRH, DRRH, XREQ, MISC, SYS, IREQL,

IREQH, LSSAL, LSSAH, LVPW, LCKR, LFRA, LPAN, LCTR, LAC, SDATAH, SDATAL,

SSR, SMOD, DMSL, DMSH, DMDL, DMDH, DCNTL, DCNTH, LVCTR, BCTR,

USBIRQ, USBBFS, USBCON, EP0CON, EP0LEN, BKCON, BKOLEN, INTCON, WEC

11

Disable unused functions and reserve “RTI”instruction for unused interrupt vectors

12

Check stack memory limited within 256 bytes.

13

Always disable interrupt function (by an ‘SEI’ instruction) when modifying the

IENAL, IENAH, IREQL and IREQH registers.

14

Use a ST2203U real chip, together with the emulation mode, to development the

whole system. Test and verify every condition