Programming the 3com/USR PalmPilot

Programming Model

• CPU: Dragonball 68328 (cpu32)
• 32 bit, little endian
  #pragma pack(2)
• RAM 128k..1M, 1M/2M ROM

Mary Chung's Menu app

GUI

• Mac heritage
• resource compiler
• dynamic resources
  FORM # AT (coords)
  USABLE, MODAL, HELPID #, MENUID #
  TITLE "Mary Chung's"
  LABEL "Mary Chung's Menu" 2000 CENTER 15
  POPUPTRIGGER "soup?" ID 3000 AT (coords) LEFTANCHOR
  LIST "soup?" "suan" "wonton" "H&S" "H&S w/wonton"
  "Egg Drop" ID 3001 AT (coords) VISIBLEITEMS 6 NONUSABLE
  POPUPLIST ID 3000 3001

Setup

DWord PilotMain(Word cmd, Ptr cmdPBP, Word launchFlags)
{
EventType e;
short err;
FormPtr fp = 0;
if (cmd != sysAppLaunchCmdNormalLaunch) { /* 0 */
return 0;
}
FrmGotoForm(1000); /* main page */

Main Loop

while(1) {
EvtGetEvent(&e, 100);
if (SysHandleEvent(&e)) continue;
if (MenuHandleEvent((void *)0, &e, &err)) continue;
switch (e.eType) {
case frmLoadEvent:
FrmSetActiveForm(fp=FrmInitForm(e.data.frmLoad.formID)); break;
case frmOpenEvent:
FrmDrawForm(FrmGetActiveForm()); break;
case menuEvent:
FrmAlert(1000); break; /* alert 1000 */
case appStopEvent:
return 0;
default:
FrmHandleEvent(FrmGetActiveForm(), &e); break;

Handle Popups

case popSelectEvent:
/* this one *actually* handles the popup menu, so recalc here */
FrmHandleEvent(FrmGetActiveForm(), &e);
updatePopup(fp,&e);
break;
case ctlSelectEvent:
FrmHandleEvent(FrmGetActiveForm(), &e);
{
if (e.data.ctlSelect.controlID == 4100)
clearEntries(fp);
}
}
}
return 0;
}

Popup

static void updatePopup(FormPtr fp, EventType *e)
{
Word lid = e->data.popSelect.listID;
ListPtr lp = FrmLookupPtr(fp,lid);
int pr, oldpr;
switch (lid) {
case 3251: /* dishsplit */
oldpr = dishprice / dishsplit;
dishsplit = lp->currentItem;
if (dishsplit == 0) dishsplit = 1;
pr = dishprice / dishsplit;
break;

Memory Management

• stack size set in pref resource
• no malloc
• database pages
• read-only pages
• calls limited to 32k

Communications

• direct serial
  error = SysLibFind("Serial Library", &SerialRef);
  if (error) ErrDisplay("Error trying to load the serial library");
  error = SerOpen(SerialRef, 0, Baud);
  if (error) ErrDisplay("Error serial open");
  error = SerReceiveCheck(SerialRef, &numBytes);
  if (error) ...
  error = SerReceive(SerialRef, buffer, numBytes, -1);
• conduits
• interface to existing programs (money extract)

Event Management

SysHandleEvent
NullEvent
frmLoadEvent
menuEvent
FrmHandleEvent
Search

Debugging

• Xcopilot
• gdb
  target pilot /dev/cua0

Last processed: 1998-02-03T02:47:14