Errata for C501/C500 data sheets for Embedded System Design

Errata: C500 Microcontroller Family Architecture and Instruction Set User's Manual 04.98

In Figure 1-2 Internal Data Memory Organization on page 1-4, there are several bit addresses that are backwards in the chart. See the bits of bytes 88H, 98H and A8H of the Internal SFR Area. 88 needs to be swapped with 89, 8B with 8C, 98 with 99, 9B with 9C, A8 with A9, and AB with AC. There is also an incorrect address in byte 2FH; bit 2F.3 is incorrectly listed as 3B, when it should actually be 7B.

On page1-6, a sentence in Section 1.2.3, paragraph 1 reads "The SFRs which are located at addresses with address bit 0-2 equal 0 (addresses 80H, 88H, 90H, ....F0H, FFH) are bitaddressable SFRs (see also figure 1-1)." It should read "The SFRs which are located at addresses with address bits 2-0 equal 0 (addresses 80H, 88H, 90H, ....F0H, F8H) are bit addressable SFRs (see also figure 1-1)."

On page 2-4, the third line in bold font reads: "Special Function Register DPSEL (Address D0h)." The correct address should be 92h, not D0h.

Errata: C501 User's Manual 04.97

On page 2-2, Section 2.1, paragraph 4: "BDC-decimal-add-adjust" should be
"BCD-decimal-add-adjust".
On page 5-1, a paragraph incorrectly describes the proper connections of the automatic power-on reset circuitry. It reads: "A pullup resistor is internally connected to VCC to allow a power-up reset with an external capacitor only. An automatic reset can be obtained when VCC is applied by connecting the RESET pin to VSS via a capacitor."
It should read: "A pull-down resistor is internally connected to VSS to allow a power-up reset with an external capacitor only. An automatic reset can be obtained when VCC is applied by connecting the RESET pin to VCC via a capacitor." In other words, the external capacitor should be connected between VCC and the RESET pin on the C501.

Errata: Philips 80C51 Family Programmer's Guide and Instruction Set