I, probably, know what it is with another name, but not that one.

Erik

FPDAT = 0x01
Read FPDAT == 0xD
Read FPDAT = first Unique ID

FPDAT = 0x02
Read FPDAT == 0xD
Read FPDAT = second Unique ID

i use usb debug adapter

He is talking about chip ID, returned over JTAG / C2 interface.

x893,

> chip return zeros Unique ID after flash programming (C8051F342).

Post the code you've FLASHed to the 'F342.
Sound like it is "dangerous" code, such as,

- 'F342 shares C2D pin with P3.0. When the code makes P3.0 push-pull, C2 interface is disturbed.
- C2 interface relies on internal OSC. When the code stops internal OSC without any other alternative, C2 interface hangs.

When the cause is revealed, we could deal with it.

I have no idea what that means

Erik

Ah, I see.
You are making your custom "programmer" pod for 'F342.

Before writing to FLASH, enable VDD monitor (VDM0CN.VDMEN) and set it on RSTSRC (RSTSRC.PORSF)

Visit to this topic, for example. It discussed about F527. You'll need similar procedure before starting FLASH erase/write operation.

Writing to flash using C2
http://www.cygnal.org/ubb/Forum1/HTML/002631.html

I try make next command sequence

1. C2_WriteAR(0xFF)
2. C2_WriteDR(0xE0)
3. C2_WriteAR(0xFF)
4. C2_ReadDR() = 0xDC (VDMEN = 1 (0x80) and VDDSTAT = 1 (0x40) other bits not described in datasheet)
5. C2_WriteAR(0xEF)
6. C2_WriteDR(0x02)
7. C2_WriteAR(0xEF)
8. C2_ReadDR() = 0x01 (! always return 01, i try write 0x06, 0x20, 0x80)
-- Now chip erase
9. C2_WriteAR(0xAD)
10. C2_WriteDR(0x03)
11. WAIT_InBusy()
12. WAIT_OutReady()
13. C2_WriteAR(0xAD)
14. C2_ReadDR() = 0x03 (!!! except 0x0D as on normal programmed chips)

Also i try set FLKEY via C2
C2_WriteAR(0xB7)
C2_WriteDR(0xA5)
C2_WriteDR(0xF1)
C2_ReadDR() = always 0xFC (bit 0-1 = 0 indicate Flash is write/erase locked)

// C2 Registers
#define  FPDAT  0xAD  // <------- for 'F34x
C2_WriteAR(0xFF);     // VDM0CN = 0x80; // enable VDD monitor
C2_WriteDR(0x80);
C2_WriteAR(0xEF);     // RSTSRC = 0x02; // set VDD monitor on RSTSRC
C2_WriteDR(0x02);
                      // enable FLASH operation mode
C2_WriteAR(FPCTL);    // write first and second key to FPCTL
C2_WriteDR(0x02);
C2_WriteDR(0x01);
Timer3us(20000);      // delay 20 ms
C2_DeviceErase();     // erase device - see AN127SW.zip

unsigned char status; // FPI status information holder

C2_WriteAR(FPDAT); // Select the FLASH Programming Data register
// for C2 Data register accesses
C2_WriteDR(DEVICE_ERASE); // Send Device Erase command
Poll_InBusy; // Wait for input acknowledge

// Check status before starting FLASH access sequence
Poll_OutReady; // Wait for status information
status = C2_ReadDR(); // Read FLASH programming interface status
if (status != COMMAND_OK)
return 0; // Exit and indicate error

Here status = 0x03 - not a COMMAND_OK !

Mitek