HP15c CE Enhanced at the same price as standard - until Oct. 10 - Limited units

Retrieving firmware

Warning: the firmware within your calculator is a copyrighted item. You may not trade or exchange this firmware, although you can keep a personal copy of it.

We assume that you have already installed SAM-BA 2.18 and properly connected your calculator to Windows, so that it appears in the Device Manager. If not, please refer to the original page How to use the programming cable.

First of all, note down the checksum of the firmware in your calculator. To do so, switch the calculator off, and, while pressing g+ENTER, press "on". You get to a menu: " 1.L 2.C 3.H ". You press 2 to get to the checksum. Note down the hexadecimal number.

  • The original firmware that came with the HP15c had a checksum 9090h.
  • The modified firmware we will propose in Modifying firmware to fix the DEC bug has a checksum AF90h
  • The firmware that we send with our enhanced HP15c (which fixes the DEC bug AND changes the rebound time from 80ms to 100ms) has a checksum 0A0Ah

Steps:

1. Start the SAM-BA 2.18 software. It initially starts very small in my computer, so you will have to extend it below and to the sides.

2. Choose the serial port that you have seen in the device manager.

3. Choose the model to be programmed:sam4l-ek[not factory programmed]

4. Press Connect. If everything is ok, you should get the screen below:

5. Make it bigger so that you can see all the fields:

6. Choose a file name in the Receive File Name box. First look where it will be stored clicking on the folder icon on the right.

7. Put 0x04000 in the Address field, to place the pointer at the start of the user firmware and after the booting firmware of the Atmel processor.

8. Put 0x1C000 as Size (for receive file)

9. Press on Receive File button

10. Check on File Explorer if you have a file with the name you selected and with size 112 KB (114.688 bytes). If so, then you're done !!

11. Press reset on the cable. Press "on" on the calculator keyboard. You should see "pr error". Your user memory has been cleared. Press any key and you'll see 0.0000.

Retrieving firmware